consolidation of self-reinforcing composites and...

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Mohammed Khan

Matric No: 0604863

MSc Project

Title:

Consolidation of Self-Reinforcing Composites and Testing of Mechanical Properties.

Under Dr. Phil Harrison

Mechanical Engineering Dept

University of Glasgow

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CONTENTS

1. Abstract …………………………………………………. 2

2. Introduction to Material ………………………………… 3

3. Material Interest, Properties and Recycling ……………. 4-5

4. Thermal Press and Manufacturer Details ………………. 5-6

5. Previous Project Overview ……………………………... 6-7

6. Thermocouples Calibration …………………………….. 8-9

7. Temperature Calibration of Platens …………………….. 9-13

8. Cooling Analysis and Water Flow Rates ……………….. 14-17

9. Temperature between Samples …………………………. 18

10. Pressure Gauge Working and Pressure Calculations …… 18

11. Preliminary consolidations ……………………………… 19-22

12. Consolidation of Test Samples …………………………. 23-25

13. Standards Followed …………………………………….. 26

14. Test Specimens …………………………………………. 27

15. Tensile Testing …………………………………………. 29-30

16. Results ………………………………………………….. 31-43

17. Conclusions …………………………………………….. 44

18. Problems Faced & Solutions …………………………... 45

19. Acknowledgement ……………………………………… 46

20. References ……………………………………………… 47

21. Appendix 1 & 2 ………………………………………… 48

22. Appendix 3 …………………………………………….. 49-54

23. Appendix 4 …………………………………………….. 55-79

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Abstract Self-Reinforcing Composites referred to SRC are a relatively new class of thermoplastics which contains a high polypropylene core called as polymer and a low melting PP called as co-polymer. The bond between the higher melting polypropylene core and the lower melting copolymer combination the polymers give a large thermal processing window. This combination is done by thermoforming process known as Co-extruded SRC.[1] The project is carried out to determine ‘Consolidation process of SRC with time dependent deformation and to investigate Mechanical properties’ of consolidated material. Availability of machines in our department to consolidate polypropylene woven sheets in to laminates is thermal press, investigate mechanical properties is universal tensile testing machine. The water cooled aluminium platens manufactured and installed to the thermal press which is to be used currently for consolidation of SRC, was done by one of the previous students. These are owned by the mechanical department of the university to drop temperature during the consolidation of SRC. Though the platens were installed, water experiments could not be executed as the O-rings used in between the platens to stop water leakage arrived after the completion of the project by previous student. Reassembled platens to press which were manufactured to be easily fitted. Carried out few experiments, by water flow to check leakages. Leakage was found from nozzle threading which was later fixed using pressure resistant tape (Teflon tape). Platens were adjusted accordingly to achieve even temperatures on the surface. The consolidation of SRC was carried out at different temperatures and pressures by varying number of layers to be consolidated. The press and platens manufactured were to consolidate samples of maximum area 250mm by 250mm. However the samples were changed to 200mm x 200mm and 150mm x 150mm to check the dark borders which were due to high pressure. After consolidation of the samples mechanical properties have been analysed by conducting tensile testing. Testing was conducted on tensile testing machine available in the department at crosshead speed of 10mm/min using ASTM D638 which is technically equivalent to BS ISO 527. Dog bone or dumbbell shaped test specimens have been prepared according to ASTM D638 standards. Finally, the anisotropic properties have been characterized by testing the test specimens in two different angles at 0 degrees and 45 degrees. The results have been analysed at both water cooling and atmospheric cooling procedures. Tensile strength has been calculated and plotted in form of graphs which represents the experimental data.

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Introduction The material department interested in investigation is SRC (self- reinforcing composite) polypropylene. This material is known as new class of thermoplastic composite, which has a fibre and matrix composed of same material. Trade name of this material is ‘Armordon’ produced by company named Don & Low one of the Scotland’s oldest companies and presently one of the leading European manufacturers of Polypropylene based textiles. The composites are mainly classified into two types (i) Co-extruded and (ii) Hot compacted. The one currently working on is Co-extruded polypropylene. Some other polypropylene based material is ‘Curv’ from Propex Fabrics which is hot-compacted type polypropylene. A co-extruded polypropylene tape consists of 3 distinct layers; 2 lower melting point copolymer PP called as ‘cap’ or co-polymer coats on each outer surface. This is encapsulated with a high melting PP core called as polymer. The layers are combined during the co-extrusion process, the bond between the higher melting polypropylene core and the lower melting copolymer PP outer cap coat layers is very strong. During subsequent downstream thermal processing the co-polymer melts fusing to polymer fabric together. The higher melting polymer core remains unaffected by the processing heat and retains its excellent properties. The combination of polypropylene polymers with different melting points gives a large thermal processing window. The tapes are highly orientated to give optimum physical properties. Alternatively the tapes are woven into a fabric. Single or multiple layers of this fabric can be thermally consolidated into laminates or panels. [1]

Curv is manufactured by Propex Fabrics. Extruded polypropylene film is stretched into tapes with exceptionally high stiffness and strength. These tapes are then woven into fabrics and undergo a patented hot compaction process in which the surface of every tape is partially melted, creating a matrix which bonds the tapes into a self-reinforced composite.[2]

The SRC are expected to retain good mechanical performance which we are currently investigating due to better interfacial bonding between fibre and matrix[ ]. The project is taken for further investigation of SRC mechanical properties after consolidation with time dependent deformation at different temperatures and changing number of layers randomly. The polypropylene sheets provided by Don & Low consists dense and are highly-crystalline. PP refers to polypropylene in this report, PP woven sheets (fibre) coated with thin layer of low-crystalline PP co-polymer, which acts as matrix phase to SRC. To resemble like carbon these sheets have been dyed in black colour. SRC refers to Self Reinforcing Composite fibre which is polymer embedded with an amorphous polymer matrix which is co-polymer, where the matrix material and reinforcing polymer are made up of same monomer units. The co-polymer (matrix) material has low –crystalline and a low melting temperature when compared to reinforcing fibres, fibre material has a high –crystalline and high melting temperature and is anisotropic. If crystalline level differs, higher melting temperatures are observed for reinforcing fibres. Significantly the matrix material due to low glass

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transition and low crystalline melt at low temperatures surrounding the reinforcing fibres intact and solidify ‘fix’ making continuous phase between fibres which referred to as first criteria for effective composite performance. Consolidation transforms a flexible SRC fabric into a rigid product. This consolidation requires pressure and temperature for bonding of matrix material [3]. Material Interest SRC materials are expected to have good mechanical properties due to interfacial bonding between fibre and matrix [4]. The matrix holds fibre together even though fibres are strong they can be brittle under stress conditions. In simple words matrix adds toughness to composite. Fibres have good tensile strength however the disadvantage is they have low compression strength. Matrix provides additional compression strength to the composite. Fibres are of interest even though they have good and bad points. One of the main reasons is they contain glass in most popular fibre which are really cheap. The glass content in fibres is spun into tiny fibres due to which they are really strong and flexible [5-6]. The other point of interest in fibres is they are recyclable without any issues hence cost effective. Material Properties SRC have good chemical and mechanical properties. Most commercial polypropylene has an intermediate crystalline between low density polyethylene and high density polyethylene. Due to which it is less flexible than low density polyethylene and less brittle than high density polyethylene. This property is the main reason for replacement of engineering plastics with polypropylene i.e.; SRC material. Polypropylenes have a very good resistance to fatigue due to which most of the flip-top bottles. Due to good dielectric properties this material is used with high performance pulse and low current loss capacitors [7]. Polypropylene has a melting point of 165 degrees due to this characteristic property many medical and laboratory items are made with this material[7]. Applications Polypropylene is a thermoplastic polymer made by chemical and textile industries, which are used in vast applications like food packaging, ropes, textiles and plastic parts, reusable containers of various type, laboratory equipments, loudspeakers, automotive components, and polymer bank notes. They are used as insulation for electrical cables in low ventilation environment preliminary tunnels. The companies that are normally involved in the manufacturing of polypropylene material take this phenomenon into consideration [8]. Major applications after investigations and research on mechanical properties will be used in automotive fields specially for interior and under hood applications like head liners as thin as 1mm to offer increased heat impact protection and maximise noise abatement. Another application after doing ballistics testing on this material is to implement this product as bullet proof jackets for military purpose [9].

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Recycling The major issue for any material or product in current life is recycling. Polypropylene is easy for recycling. The companies that are normally involved in the manufacturing of polypropylene material take this phenomenon into consideration. Recycled polypropylene can be used for packing containers and recycled fibres can be used into new products. On one hand mechanical recycling is considered as the best recovery option for large polypropylene automotive components, on the other hand, energy recovery is solution for most small plastic parts. Blending of recycled polymers may help to improve properties of materials. Recycled polymers may vary in compositions and poor properties but additives can be used to improve properties. Recycling of polymers is beyond any doubt in this industry will be looking for environmentally friendly and cost effective alternative [10]. Thermal Press The thermal press currently working on for consolidation of SRC is a hydraulic thermal press; source for heating up the press is electricity. Model of thermal press is S10316/95.

Fig 1 Thermal Press.

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Thermal press manufacturer is Mackey Bowley International shown in Fig 1who is one of the UK’s companies known as specialist in designing and manufacturers of custom built hydraulic presses for major industries in both new and used/rebuilt hydraulic presses. They also manufacture guillotines for polymer industries. They manufacture vast range of presses like -Extrusion Presses -Composite Presses -Multi Station Moulding Presses etc.; Contact Details: Mackey Bowley International Gravesend, Kent. DA12 2PT UK Phone: +44 1474 363521 Website: www.mackeybowley.co.uk Previous Project Overview Project was undertaken by a student named Andrew Cochrane to design, manufacture and installation of water cooled platens to the thermal press. Aim of this project was to provide active cooling to SRC during consolidation. Thermal press cools down very slow after the heater turned off by convection and radiation of surrounding atmosphere. The press contains 4 heaters in upper and lower moulds 8 in total. As shown in Fig.2 this provides required temperature.

Fig 2 Heaters inside Thermal Press Mould.

The implementation of water cooled platens will allow rapid temperature drop in a controlled manner. The material selected for these platens is Aluminium. The platens are designed to have even temperature on surface as much as possible. To acquire this platens are manufactured having two channels which contains one inlet and one outlet to each channels. Reason for these channels is to introduce water with same flow rate in opposite directions at same time, which will result in more even temperature distribution than water flowing through both channels in same direction. Also the inlet was designed lower than outlet intended to reduce trapping of air inside platens during water flow. As shown in Fig 3, the platens have rounded corner channels which will drop the water pressure.

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Fig 3 Aluminium Platens.

The platens are manufactured as a pair one for upper and other for bottom half of the thermal press. Each half is sub manufactured in two halves which is assembled by screws this is done to provide an O-ring between them to avoid water leakage during water flow. The overall dimensions of the platens are 305 x 305 mm equivalent to the press plates. Maximum size of 250 x 250 mm sample can be consolidated on these platens. The platens were simulated using Finite Element Analysis software, temperature distribution was also analysed at both steady and transient conditions. The consolidation of SRC has been conducted but did not conduct any experiments using water flow through platens as the O-rings did not arrive in time. The press shown in Fig 4 is after assembling of platens along with nozzles and heat resistant pipes.

Fig 4 Thermal Press after assembling of platens.

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Disassembled and reassembled platens to press using O-rings between platens before starting the current project. Thermocouples Calibration To conduct temperature calibration over the platen surface thought of calibrating the thermocouples to check if there is any error before moving further. This has been done using boiled water and glass thermometer. The available numbers of thermocouples were 6 but realised one was not working so ignored that and calibrated remaining 5. Boiled the water to 100 degrees as recorded on the thermometer then introduced the thermocouples in the hot water and recorded temperature for every 10 degrees in a decrement order, refer Appendix 1 for readings, but plotted in ascending order in graph for easy understanding. According to the Figure 5 below there was not much difference in thermocouples when compared to thermometer, thinking which is negligible.

Thermocouples calibration using glass thermometer

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1 2 3 4 5Seies of thermocouples

Tem

p (

0 C)

ThermometerProbe 1Probe 2Probe 3Probe 4Probe 5

Fig 5 Thermocouples Calibration with glass thermometer.

The surface temperature is been tested using the calibrated thermocouples. Set temperature is referred to dial temperature of press in this report. Set temperature to 160 degrees and recorded the reading on surface of platens by placing the thermocouples at different positions and also at a single position. Recorded temperature of thermocouples at a fixed position by placing two thermocouples at same time is shown in Table 1 below

Position Top-- -Platen Bottom-- -Platen Probe 1 Probe 2 Probe 3 Probe 4 Centre 154 155 153 152 Corner 154 154 150 152

Table 1 Probe readings at set temperature. The readings were recorded as soon as the set temperature reached to 160 degrees left it for 15 minutes to record the actual temperature. As shown in Table 2 the actual temperature recorded

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Position Top-- -Platen Bottom-- -Platen Probe 1 Probe 2 Probe 3 Probe 4 Centre 154 155 155 155 Corner 155 154 155 154

Table 2 Probes reading actual temperature at different positions. This shows that the average temperature along the surface of top and bottom platens at set temperature is 155 degrees. The temperature was checked by interchanging the probes on platens simultaneously, recorded the same. This confirms that the thermocouples were working fine so have used the same thermocouples further. Temperature Calibration of Platens (Heating) Platen temperature was calibrated to find actual temperature on surface at different set temperatures. Set temperature is referred to dial temperature of press as shown in Fig 6, internal probe is the temperature read by dial during heating. Set temperature to 50 degrees on dial time taken to reach this temperature is recorded as 10min and 30sec, where no thermocouples have been used during this because set temperature shows up on dial of press.

Fig 6 Dial of thermal press.

When the set temperature has reached 50 degrees placed the thermocouples and recorded the temperature at different positioning on platen surface. Refer Fig 7 for thermocouple positions.

Fig 7 Positions of thermocouples.

Internal Probe

Set Temperature

Top Platen

Bottom Platen

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Temperature recorded on the platens surface at this time was Top platen 43.5 degrees and Bottom platen was 42.5 degrees, there was a difference of one degree between both platens may be due to heaters or convection. The platens were left for 15-20 min to record the actual temperature at this set temperature. Recorded temperature after this time was top platen 47 degrees and bottom platen 46 degrees; this is the actual temperature after which the temperature was constant. Plotted a graph for easy understanding, refer to Fig 8. The overall temperature difference between two platens is 1degree considering it to be acceptable. The calibration is done at various different temperatures to figure out the actual temperature.

Temperature calibration of Platens @ 50oC set on dial

43.5

4646.5

47 47 47 47

42.5

4545.5 45.5

46 46 46

42

43

44

45

46

47

48

0 10 20 30 40 50

Time in min

Tem

p (o C

)

Top

Bottom

Fig 8 Temperature calibration@500C

• Set temperature 70 0C • Time taken to reach from 50 0C is 9 min. 10 +9 = 19min • Actual temperature, top platen 67.5 0C and bottom platen 66.5 0C • Refer Fig 9.

Temperature calibration of Platens @ 70oC set on dial

64.5

66.5

62.5

64.5

65.5

6767.5 67.5 67.5

66.5 66.5 66.5

62

63

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65

66

67

68

0 5 10 15 20 25 30 35 40 45

Time (min)

Tem

p (

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TOP

BOTTOM

Fig 9 Temperature calibrations @700C

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• Set temperature 90 0C • Time to reach from 70 0C is 9 min. 19 +9 = 28min. • Actual temperature, top platen 86.5 0C and bottom platen 85.5 0C • Refer Fig 10.

Temperature Calibration of platens @ 90oC set on dial

82.5

86.586.586.586.586.5

84.585.585.585.5

8584.5

82

83

84

85

86

87

88

89

90

0 10 20 30 40 50 60

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p ( 0

C)

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BOTTOM

Fig 10 Temperature calibration @ 900C

• Set temperature 120 0C • Time taken to reach from 90 0C is 14 min. 28 + 14 = 42 min • Actual temperature, top platen 116.5 0C and bottom 114.50C • Refer Fig 11.


112

116.5116.5116.5116.5116.5

114.5114.5114.5114.5114.5

114

111112113114115116117118119120

0 10 20 30 40 50 60 70 80Time (min)

Tem

p (

0 C)

TOP

BOTTOM

Fig 11 Temperature calibrations @120 0C

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• Set temperature 150 0C • Time taken to reach from 120 0C 15 min. 42 + 15 = 57min • Actual temperature, top platen 145.5 0C and bottom platen 143.5 0C • Refer Fig 12.


140.5

143.5143

145145.5 145.5 145.5 145.5

143.5 143.5 143.5 143.5

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144

145

146

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Time (min)

Tem

p (0 C

)

TOP

BOTTOM

Fig 12 Temperature calibrations @150 0C

• Set temperature 170 0C • Time taken to reach from 150 0C is 12min. 57 + 12 = 69min • Actual temperature, top platen 164.5 0C and bottom platen is 162.5 0C • Refer to Fig 13.


160

162.5

164.5164.5164.5164.5

163.5

161.5162.5

162.5162.5162.5

159160161162163164165166167168169170

0 10 20 30 40 50 60 70 80 90 100

Time (min)

Tem

p (0 C

)

TOP

BOTTOM

Fig 13 Temperature calibrations @ 170 0C

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Calibration tests conducted at different temperatures observed that time taken to reach actual temperature after reaching set temperature is approximately 15min. Noticed temperature difference before 100 degrees is noted to be 1 degree between top and bottom platens after 100 degrees has increased to 2 degree, this might be due to heat loss around the platens or might be due to heaters or heat convection. Further tests are required using thermal insulation around the platens to make sure why is it happening so. Empirical formula for Actual Temperatures Equation has been derived to calculate the actual temperature at any set temperature, the equation is in form of y = m x + c, where m and c are constant ‘x’ is set temperature. Refer to Fig 14 for temperature differences between Top and Bottom platens. For top platen it is y = 1.0217 x + 1.4763 Accuracy is 0.99 % For bottom platen it is y = 1.0329 x + 1.8582 Accuracy is 0.99 %

Equation for Actual Temp

47

67.5

86.5

116.5

145.5

164.5162.5

143.5

114.5

85.5

66.5

46

y = 1.0217x + 1.4763R2 = 0.9999

y = 1.0329x + 1.8582R2 = 0.9999

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0 20 40 60 80 100 120 140 160 180

ACTUAL TEMP (0C)

SE

T T

EM

P (0 C

)

TOPBOTTOMLinear (TOP)Linear (BOTTOM)

Fig 14 Empirical formulae for actual temperature.

After temperature calibration of platens was easy to figure out the actual temperature at any set temperature.

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Cooling Analysis of Platens Cooling analysis of platens was carried out to study the cooling behaviour. Cooling analysis of platens was done at a fixed set temperature 150 0C, but cooled by different sources. The three main sources easily available were water flow cooling, compressed air flow cooling and atmospheric cooling.

(i) Water cooling process Water cooling process was done at set temperature 150 0C after reaching actual temperature which was 144.5 0C at an average of top and bottom platens. Before doing this the water flow rate from tap, inlet and outlet nozzles was measured. All the flow rates were measured using a 500 ml glass beaker. Refer to Fig 15.

Fig 15 Measuring water flow using glass beaker.

The water flow rate from tap has been measured Refer Appendix 2 for flow rate readings. Refer Fig 16 for flow rate from tap.

Flow rate measure from Tap

33.07

26.64

14.76

20.47

33.84

27.45

14.53

20.47

y = 16.355x - 38.188R2 = 0.9993

y = 15.393x - 20.537R2 = 0.9991

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0 10 20 30 40Time(sec)

mea

sure

men

t(ml)

Left(Top)Right(Bottom)Linear (Left(Top))Linear (Right(Bottom))

Fig 16 Water flow rate from tap.

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Water flow from left tap is supplied as inlet to top platen and right to the bottom. Using the empirical formula from Fig 16 the water flow rate can be calculated.

y = 16.35 x – 38.18 Accuracy = 99% ’x’ is volume of water in ml. Water flow rate for Bottom platen can be calculated by using formula y = 15.39 x – 20.53 Accuracy = 99% Refer to Fig 17 for water flow rate for inlet and outlet of platens and Appendix 2 for water flow readings from tap, inlets and outlets.

Water input to platens

y = 27.555x + 7.21R2 = 0.997

y = 28.627x - 8.0579R2 = 1

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0 2 4 6 8 10 12 14 16 18 20

Time (sec)

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er m

easu

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ent (

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Bottom

Fig 17 Water flow rate to inlet of platens (Top and Bottom).

Water flow rate at inlet to both top and bottom platens were measured and flow rate for top platen can be calculated by using the empirical formula y = 27.555x + 7.21 Accuracy = 99% Similarly for bottom platen y = 28.627x - 8.0579 Accuracy = 1% Water flow rate for outlet of the platens both top and bottom was measured using the same 500ml glass beaker. Refer to Fig 18.

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Water output from platens

y = 7.7339x - 17.399R2 = 0.9984

y = 17.151x - 8.2398R2 = 0.998

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Time (sec)

Mea

sure

men

t (m

l)

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Bottom

Fig 18 Water output from platens (Top and Bottom).

Water flow rate at outlet of top platen can be measured by using the empirical formula y = 7.7339x - 17.399 Accuracy = 99% Similarly for bottom platen y = 17.151x - 8.2398 Accuracy= 99% Noticed that the water flow from the bottom platen is very high at out let when compared to inlet this might be due to the bottom platen being lower than the top platen. After measuring the flow rates the water was passed through the platens after the platens reached actual temperature. Noticed that there was only steam coming out till there is a temperature drop of 50 degrees from 150-100 degrees, after which there was a continuous flow, time taken to get the temperature down from 150 – 21 degrees that is room temperature is 37min refer to Fig 19 for temperature drop and empirical relation. The empirical has been found to calculate time for temperature drop during water cooling process is y = -3.4169 x + 143.21 Accuracy = 99%

(ii) Compressed air cooling process After water cooling used compressed air to make sure no water left in platens, and then set temperature back to 150 0C to conduct compressed air cooling. Time taken to reach this temperature was 57min due to very less quantity of water left in platens which did not make big difference reaching the set temperature, observed steam coming out at temperature 102-120 degrees. Recorded actual temperature which was 144.5 0C on an average of top and bottom platens, where top platen was 145.5 0C and bottom platen was 143.5 0C. Then using low HP air compressor the compressed air

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has been passed through inlets of both top and bottom at a constant pressure, the outlets were left open in atmosphere. Recorded time to drop temperature from 150 0C to room temperature that is 21 degrees took 122mins refer to Fig 19 for temperature drop and empirical relation. The empirical has been found to calculate time for temperature drop during compressed air cooling process is y = -1.0481 x + 149.86 Accuracy = 99%

(iii) Atmospheric cooling process To conduct atmospheric cooling raised set temperature back to 150 0C. Recorded actual temperature to be same as before. The platens were left open to cool down at room atmosphere and convection. Recorded time taken to reach room temperature from 150 0C was 136min. Refer to Fig 19 for temperature drop and empirical relation. The empirical relation has been found to calculate time for temperature drop at atmospheric cooling process is y = -0.9361 x + 149.86 Accuracy = 99%

Temperature Cooling Measurement of Platens

0

80

109

136

48

24

122

98

69

53

2600

5

11

19

27

37

y = -1.0481x + 149.9R2 = 0.9986

y = -0.9361x + 149.86R2 = 0.9993

y = -3.4169x + 143.21R2 = 0.9905

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0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150

Time (min)

Tem

p (0

C)

AIR

ATM

WATER

Linear (AIR)

Linear (ATM)

Linear (WATER)

Fig 19 Cooling rates of platens at water, compressed air and atmospheric.

After conducting tests for temperature drop noticed that there was faster drop in temperature by using water flow than compressed air and atmospheric cooling. The compressed air cooling process was almost similar to atmospheric cooling, hence decided to consolidate samples using water cooling and atmospheric cooling for further investigation of mechanical properties in fast cooling and slow cooling.

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Temperature Calibration of Sample (Heating) After study of cooling rates a sample has been pressed within the thermal press at 150 0C set temperature to check temperature between layers of SRC regardless of consolidation and applied a very less pressure of around 20 bars. Placed two thermocouples after 7 layers of SRC while the sample was of 15 layers. The sample was placed within the press after reaching the actual temperature which was 145 0C, after 2-3 minutes the sample was removed as the insulation of thermocouples was burning and noticed that the sample was trying to consolidate along with the thermocouples. Recorded temperature before removing the sample was 144.5 0C on an average, as one of the thermocouple was reading 144 0C and the other 145 0C which was almost equal to the actual temperature. Pressure Gauge Working and Calculations Thermal press contains a pressure gauge which reads the pressure of fluid acting on the piston, as the piston moves in upward direction. The pressure on sample varies as the area of platens is different. As shown in Fig 20 the pressure gauge reads two types of units:

1. Pressure in Bars 2. pressure in Psi

Fig 20 Pressure gauge of thermal press.

Preferred pressure in bar in this project. When the pressure is set to 100 bar the pressure acting on the sample is calculated as: Diameter of piston for current press model is = 154.2 mm Area piston = �/4 d2 = �/4 (0.1542) 2 = 0.0186 m2 Area Sample = 250 x 250 mm = 0.25 x 0.25 = 0.625 m2

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Pressure on sample = pressure of piston x Area piston / Area Sample

Pressure of piston = 100bar = 100 x 105 N/ m2 Psample = 100 x 0.0186 / 0.0625 = 29.76 bar � 30 bar Using these calculations we can find the actual pressure acting on sample during consolidation. Preliminary Consolidation Experiments After study of cooling rates and temperature between samples as a trial a sample has been consolidated at set temperature 155 0C. The sample size is 240 x 240 mm, 4 layers of SRC at a pressure of 100 bars on gauge. Time taken to reach set temperature is 56 min and left for 15 min to reach actual temperature the placed 4 layers of SRC in side the press and applied pressure of 100bar and left sample inside the press for 15 min for consolidation at same temperature and then turned off set temperature and left the sample to cool down at room atmosphere. Refer to Fig 21. Observed consolidation was good, but observed dark boundary along the borders of sample, refer to Fig 22 was not able to figure out was it due to heaters or due to high pressure.

@ 155 (0C) set,Act 150 (0C), 240 x 240 mm,4 lyr

020406080

100120140160180

0 50 100 150 200 250 300 350

Time (min)

Tem

p (0 C

)

At/C

Placed Sample

Fig 21 Consolidation @ 155 0C set, Act 150 0C, Atmospheric cooled.

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Fig 22 Sample after consolidation at 1550C set temperature.

Repeated the experiment again at same conditions, but changing the pressure by 50 bars on gauge instead of 100 bars. Observed the sample to be same as before, which concludes that this is happening at all pressures. Further investigation is needed to figure out why it is happening. Conducted a few consolidation experiments, varying the sample size and water cooled process. Previously samples were consolidated with area of 240 x 240mm changed the size to 200 x 200mm and 150 x 150mm.

• Sample size: 200 x 200mm •••• Set temperature 152 0C •••• Actual temperature 147 0C •••• Pressure 100 bar •••• Sample left in mould 30min. •••• Water cooled •••• Refer Fig 23.

@ 152 (0C) set temp,Act 147 (0C), 4 lyr, 200 x 200mm

02040

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p (0 C

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Placed Sample

Fig 23 Consolidation @ 152 0C set, Actual 147 0C, Water cooled.

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• Sample size: 150 x 150mm • Set temperature 152 0C • Actual temperature 147 0C • Pressure 100bar • Sample left in mould 15min • Refer Fig 24.

@ 155 (0C) set, Act 150 (0C), 15 lyr 150 x 150mm

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Time (min)

Tem

p (0 C

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Placed sample

Fig 24 Consolidation @ 155 0C set, Actual 150 0C, Water cooled.

The boundaries along the borders of sample were noticed again, which indicates that there was high pressure acting along the borders of sample. This was due to bowing effect in the platens at the pressures applied refer Fig 25.

Fig 25 Bowing effect of platen at high pressure on sample.

Tried using aluminium foils on both sides of sample to check if this makes any changes, placed aluminium foil below and above of sample equal to sample size. Refer Fig 26.

Pressure acting on sample Sample

Platen

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@155 (0C) set,Act 150 (0C), 240 x 240mm, 4lyr.

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Time (min)

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p (0 C

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W/C

Placed Sample

Fig 26 Consolidation of sample with aluminium foil, @ 152 0C set, Water cooled. This test did not make any much difference, but in fact given a good surface finish on the sample. Tried the same test by using 4 layers of aluminium foils in middle of sample of area 100 x 100 mm, where the sample size was 240 x 240 mm. Refer Fig 26, as the procedure and temperature was same. This trial also did not make difference but it gave dark boundaries along the boundary where the aluminium foil was placed and also along the borders of the sample area. Tried a sample by removing the platens to check if any problem with platens, but noticed the same kind of dark boundaries along the borders. This makes thinking of bowing effect of the press. Reassembled the platens and consolidated a sample by placing sample diagonally to the platens to check if this makes any change. Refer Fig 26 as it was on same conditions. The sample was much better than before in spite of leaving dark boundaries along the surface it was only at 4 corners of sample. Refer Fig 27 for sample after consolidation in diagonal position.

Fig 27 Sample consolidated diagonally in press.

Dark Boundaries.

- 23 -

The use of aluminium foils did not resolve the problem, but consolidating the samples diagonally gave better result than before so decided to consolidate test samples following this procedure. Concluding that this problem was due to bowing of platens at high pressure, due to which the pressure was acting along the borders of the sample. Further simulation of platens is required to solve this problem. Consolidation of Test Samples Consolidated test samples at 4 different temperatures 140, 147, 150 and 153 degrees. From here on all the temperatures taken are referred to Actual temperatures. The set temperatures for these temperatures are 145, 152, 155 and 158 degrees. These specific temperatures have been selected to investigate Tensile strength and mechanical properties according to Korean science and engineering foundation paper. To get the samples at same test conditions consolidated three set of samples at each test conditions separating them by placing aluminium foils in between. Each sample is of size 240 x 240 mm and 4 layers, sample before and after consolidation as shown in Fig 28 placed the samples in press in diagonally along with an aluminium strip to cut test specimens for T-peel testing.

Fig 28 Consolidation of 3 samples at same test conditions for tensile strength and

T-peel testing. Test samples were consolidated at both fast cooling and slow cooling conditions at different processing temperatures.

• Sample size 240 x 240 mm • Set temperature 145 0C • Actual temperature 140 0C • Pressure on gauge 100 bar • Pressure on sample 30 bar • Atmospheric and water cooled • Refer Fig 29

Aluminium strip

Samples bottom, middle and top

- 24 -

@145 (0C) set, Act 140 (0C)

20

40

60

80

100

120

140

160

0 50 100 150 200 250 300 350

Time (min)

Tem

p (0 C

)

W/CAt/CPlaced Sample

Fig 29 consolidation of test sample @ 145 0C set, W/C and At/C


@152 (0C) set,Act 147 (0C)

20

40

60

80

100

120

140

160

0 50 100 150 200 250 300 350 400

Time (min)

Tem

p (0 C

)

W/C

At/C

Place Sample

Fig 30 consolidation of sample at 152 0C set, W/C and At/C

• Sample size 240 x 240 mm • Set temperature 1550C • Actual temperature 150 0C • Pressure on gauge 100 bar • Pressure on sample 30 bar • Atmospheric and water cooled • Refer Fig 31

- 25 -

@155 (0C) set, Act 150 (0C)

20

40

60

80

100

120

140

160

180

0 50 100 150 200 250 300 350 400

Time (mm)

Tem

p (0 C

)

W/C

At/C

Placed Sample

Fig 31 consolidation of sample at 155 0C set, W/C and At/C


@158 (0C) set,Act 153 (0C)

20

40

60

80

100

120

140

160

180

0 50 100 150 200 250 300 350 400 450

Time (min)

Tem

p (0 C

)

W/C

At/C

Placed Sample

Fig 32 consolidation of sample at 158 0C, W/C and At/C

For all temperature readings refer Appendix 3. Standards Followed ASTM D638 was the standard followed previously by Korean science and engineering foundation to investigate mechanical properties of laminated SRC, and

- 26 -

tensile strength was calculated. Preferred ASTM D638 standard again to maintain the same standards and investigate if any changes in mechanical properties by using water cooled platens. This standard is generally used for materials whose thickness is less than 1mm up to 14mm. according to this standard thin film less than 1mm test method D882 is preferred test method, but according to D882 thin films have been arbitrarily defined as sheeting having nominal thickness not greater than 0.25mm. The thickness of consolidated samples is measured to be 0.48mm which is greater as defined in D882. So has preferred to go with ASTM D638 standard, which is also technically equivalent to ISO 527. Significance and Use The test method is designed to produce tensile property data for the control and specification of plastic materials. For any material, there will be a specification that requires the use of test method for research and development purpose. Tensile properties may vary with specimen preparation and with speed and environment of testing. Apparatus A testing machine of the constant rate- of-crosshead-movement type and comprising is used as shown in Fig 33.This contains

Fig 33 Universal tensile testing machine.

- 27 -

-A fixed or essentially stationary member carrying one grip. -A movable member carrying a second grip. -Grips for holding the test specimen between the fixed member and the movable member of the testing machine preferable self-aligning type. -Self-aligning grips are attached to the fixed and movable members of the testing machine in such a manner that they will move freely into alignment as soon as any load is applied. -A load-indicating mechanism capable of showing the total tensile load carried by the test specimen when held by the grips. -An extension indicating mechanism capable of showing the amount of change in the separation of the grips, that is, crosshead movement. -Inbuilt extensometer to read the extension of specimen when load applied. Test Specimens According to ASTM D638 the test specimens are classified in to V types depending on their thickness. Thickness of current consolidated SRC is 0.48 which is less than 1 mm and as per the standard it falls in type V. Refer to Fig 34 the specimens are cut into dumbbell shaped for tensile testing also called as dog-bone shaped.

Fig 34 Test specimen as per standard.

Dimensions of type V test specimens thickness less than 1 mm are in Table 3 below.

Dimensions Type V less than 1mm (mm) W-Width of narrow section 3.18 L-Length of narrow section 9.53

WO- Width overall 9.53 LO-Length overall 63.5 G-Gauge Length 7.62

D-Distance between Grips 25.4 Table 3: Dimensions of test specimen.

Number of specimens per sample according to standards is 5 at same test conditions. Number of samples cut per sample is 3 and number of samples prepared at same test conditions is 3. Total number of specimens is 9 in total at same test conditions. To characterize the anisotropic properties the test samples at two directions (0 and 45 degree angles). As shown in Fig 35. All the specimens were managed to cut by using scissors maintaining the tolerances.

- 28 -

Fig 35 Test samples cut off from sample at 0 and 45 degrees. Speed of Testing according to standard for Type V specimens is shown in Table 4 below.

Classification Speed in mm 1

Type V 10 100

Table 4: Cross head speeds for tensile testing. Speed followed is 10 mm per min, Conditioning of test samples according to the standards is 23 ± 2 0 C, so conducted all the testing at room temperature which was 21 0C. Testing Procedure -Measured the width and thickness of each specimen to the nearest 0.025 mm using the current standard. -Measured the width and thickness of flat specimens at the centre of each specimen and within 5 mm of each end of the gauge length. -Placed the specimen in the grips of the testing machine, taking care to align the long axis of the specimen and the grips with an imaginary line joining the points of attachment of the grips to the machine. -The test samples were pulled at 90 degrees along fixed axis. - The test specimens have been pulled till the yield point and recorded the extension of specimen and maximum load applied. The test specimens before and after break are shown in Fig 36.

Specimen 1

Specimen 2

Specimen 3

- 29 -

Fig 36 Test specimens before and after testing.

-Number of test specimens for each sample tested is 3 at 0 degrees angle and 3 for 45 degrees angle and at both water cooled and atmospheric cooled. - Results are plotted as shown in Fig 33 – 35, which are for all three samples top, middle and bottom @ 140 0C and 0 degrees angle Atmospheric cooled showing the maximum load before Tensile Strength calculations. Positions of test specimens are taken are mentioned in Table 5 refer to Figure 35 for positions.

Specimens Position 1 Middle 2 Between middle and corner 3 Corner edge

Table 5 Positions of specimens and numbering.

The tensile tested specimen data is collected and according to that data the graphs are plotted to show the maximum load applied on each specimen for every sample at each processing temperature. Refer to Fig 37 for load on specimens 1, 2 and 3 for the top sample at 140 0C atmospheric cooled process.

@140 top a/c 0 degrees

0

100

200

300

400

500

600

700

0 2 4 6 8 10 12

Extension (mm)

Load

(N) 1

2

3

Fig 37 Maximum load @ 140 0C, atmospheric cooling at 0 degrees angle for top

sample.

Specimens before testing

Specimens after testing

- 30 -

Following the same procedure plotted graph for middle sample for all 3 specimens at 140 0C processing temperature atmospheric cooled process. Refer Fig 38.

@140 middle a/c 0 deg

0

100

200

300

400

500

600

700

0 1 2 3 4 5 6 7 8

Extension (mm)

Load

(N) 1

2

3

Fig 38 @ 140 0C middle sample At/C at 0 degrees angle.

Similarly plotted graph for all 3 specimens for bottom sample at 140 0C processing temperature atmospheric cooled process. Refer Fig 39.

@140 bottom a/c 0 deg

0

100

200

300

400

500

600

700

800

0 1 2 3 4 5 6 7 8

Extension (mm)

Load

(N) 1

2

3

Fig 39 @ 1400C, bottom sample a/c at 0 degrees angle.

Refer Appendix 4 for graphs showing maximum load for remaining samples. Tensile strength result calculations Tensile Strength = Max Load / Average cross sectional area of specimen

- Max load is referred to L - Cross-sectional area of specimen to A = thickness x width = 0.48 x 3.5 = 1.68

mm

- 31 -

- Tensile strength is referred to T.S Calculating the Tensile Strength At 0 degrees angle and Atmospheric cooled samples:

I. @140 degrees a/c, 0 degrees angle bottom sample: Specimen 1. T.S = L / A = 762.45 (N) / 1.68 (mm2) = 453.8 MPa (Note: As the result should be in MPa, N/ mm2 is converted into N/ m2)

Specimen 2. T.S = L/A = 682.06 / 1.68 = 405.9 MPa Specimen 3. T.S = L/A = 590.89 / 1.68 = 531.7 MPa

II. @140 degrees, middle sample: Specimen 1. T.S = L/A = 634.76 / 1.68 = 377.8 MPa Specimen 2. T.S = L/A = 641.63 / 1.68 = 381.9 MPa Specimen 3. T.S = L/A = 613.78 / 1.68 = 365.3 MPa III. @ 140 degrees Top sample: Specimen 1. T.S = L/A = 588.60 / 1.68 = 350.3 MPa

Specimen 2. T.S = L/A = 567.62 / 1.68 = 337.8 MPa

Specimen 3. T.S = L/A = 487.89 / = 290.4 MPa

- 32 -

Taking average of all 9 specimens for all top, middle and bottom samples plotted as a 10th point calculating the Standard error. Refer to Fig 40.

@ 140 (0C) 0 degrees angle At/C

250

300

350

400

450

500

550

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)Specimens

Avg

Fig 40 Tensile strength of specimens @ 140 0C, 0 degrees angle At/C.

Following the same procedure plotted the graph at same processing temperature 140 0C actual at 0 degrees position for water cooled process. The 10th specimen in graph is showing the average of all test specimens. The graph plotted along with standard error. Refer Fig 41.

@ 140 (0C) 0 degrees angle W/C

250

300

350

400

450

500

550

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg

Fig 41 Tensile strength of specimens @ 140 0C, 0 degrees angle W/C.

• @ 147 0C Actual temperature • 0 degrees angle • Atmospheric cooled • Refer Fig 42

- 33 -


250

300

350

400

450

500

550

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg

Fig 42 Tensile strength of specimens @ 147 0C, 0 degrees angle At/C

• @ 147 0C Actual temperature • 0 degrees angle • Water cooled • Refer Fig 43


250

300

350

400

450

500

550

0 2 4 6 8 10 12

Specimens

T.S

(M

Pa)

Specimens

Avg

Fig 43 Tensile strength of specimens @ 147 0C, 0 degrees angle W/C


- 34 -


250

300

350

400

450

500

550

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg




250

300

350

400

450

500

550

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg

Fig 45 Tensile strength of specimens @ 1500C, 0 degrees angle W/C


- 35 -


250

300

350

400

450

500

550

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg




250

300

350

400

450

500

550

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg

Fig 47 Tensile strength of specimens @153 0C, 0 degrees angle W/C

Taking the 10th specimen from all test conditions Graph is plotted using the standard error to show the Tensile Strength at each processing temperature. Refer Fig 48 for 0 degrees angle position for Atmospheric cooling.

- 36 -

@ 0 degrees angle A/C

250

300

350

400

450

138 140 142 144 146 148 150 152 154

Temp (0C)

T.S

(MP

a)

At/C

Fig 48 T.S for all processing temperature at 0 degrees angle At/ C.

Following the same procedure plotted graph for Water cooled process. Refer Fig 49.

@ 0 degrees angle W/C

250

300

350

400

450

138 140 142 144 146 148 150 152 154

Temp (0C)

T.S

(MP

a)

W/C

Fig 49 T.S for all processing temperatures at 0 degrees angle W/C.

Graph has been plotted to check the difference between Atmospheric cooling and Water cooled process at all processing temperatures at 0 degrees angle. Refer Fig 50.

- 37 -

0 Degrees angle A/C & W/C

250

300

350

400

450

138 140 142 144 146 148 150 152 154

Temp (0C)

T.S

(MP

a)

A/C

W/C

Fig 50 Tensile Strength at all processing temperatures 0 degrees angle both At/C &

W/C. Tensile strength for Water cooled process is not making much difference at different processing temperatures at 0 degrees angle position test specimens from samples except at 1470C. To figure out the tensile strength at 45 degrees position the graphs have been plotted following the same procedure.



20

40

60

80

100

120

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg

Fig 51 T.S for all test specimens at 1400C processing temperature at 45 degrees angle

on sample At/C.


- 38 -

@140 (0C) 45 degrees angle W/C

20

40

60

80

100

120

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg

Fig 52 T.S for specimens at 1400C processing temperature, 45 degrees angle W/C.



20

40

60

80

100

120

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg

Fig 53 T.S for specimens at 147 0C processing temperature 45 degrees angle At/C.


- 39 -


20

40

60

80

100

120

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg

Fig 54 T.S for specimens at 147 0C processing temperature 45 degrees angle W/C



20

40

60

80

100

120

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg

Fig 55 T.S for specimens at 150 0C processing temperature 45 degrees angle At/C


- 40 -


2030405060708090

100110

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg




20

40

60

80

100

120

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg

Fig 57 T.S for specimens at 150 0C processing temperature 45 degrees angle At/C


- 41 -


20

40

60

80

100

120

0 2 4 6 8 10 12

Specimens

T.S

(MP

a)

Specimens

Avg


Using 10th specimen which is average of all specimens at processing temperatures, along with the standard error plotted graph indicating tensile strength at different processing temperatures. Refer Fig 59.

45 degrees angle At/C

40

45

50

55

60

65

70

75

138 140 142 144 146 148 150 152 154

Temp (0C)

T.S

(MP

a)

At/C

Fig 59 T.S for all processing temperature at 45 degrees angle At/ C

Following the same process plotted graph for water cooled samples. Refer Fig 60

- 42 -

45 degrees position W/C

40

45

50

55

60

65

70

75

138 140 142 144 146 148 150 152 154

Temp (0C)

T.S

(MP

a)

W/C

Fig 60 T.S for all processing temperatures at 45 degrees angle W/C

To analyse the difference between atmospheric cooling and water cooling plotted results on same graph for all processing temperatures. Refer Fig 61.

45 degrees position A/C & W/C

40

45

50

55

60

65

70

75

138 140 142 144 146 148 150 152 154

Temp (0C)

T.S

(MP

a)

A/C

W/C

Fig 61 T.S for all processing temperatures for 45 degrees angle for both At/C & W/C. The tensile strength is seen to be high in water cooled samples when compared to atmospheric cooled samples except at 153 0C processing temperature. T-peel strength results from same test sample at same processing temperature from VIkram Karnam report who was working on investigation of T-peel strength. Refer Fig 62.

- 43 -

Fig 62 T-peel strength at different processing temperatures.

T-peel strength comparision between Water cooled & Atmospheric cooled specimens

0.200

0.300

0.400

0.500

138 140 142 144 146 148 150 152 154

Temperature (oC)

T-p

eel s

tren

gth

(N

/mm

)

Water cooled

Atm cooled

- 44 -

Conclusions

- Aluminium platens made a difference in saving time during consolidation and also good temperature distribution over the surface. However need further simulation to resolve the problem of bowing when high pressure applied

- As the processing temperatures were increased, tensile strength decreased in

both atmospheric and water cooling process at 0 degrees. No much difference in tensile strength except resulting high tensile strength at 150 0C during water cooled.

- High tensile strength for water cooled samples when compared to atmospheric

cooled at 45 degrees angle except at 153 0C. This might be due to good bonding between matrix-matrix of SRC during consolidation in very less time at water cooled process.

- High peel strength at all processing temperatures for water cooled samples

when compared to atmospheric cooling process.

- According to results this indicates that there is a good improvement in properties of SRC with water cooling process resulting with high tensile strength at 45 degrees angle and high T-peel strengths.

- Finally concluded that water cooled process can be used in future for good

results and improved mechanical properties of SRC.

- 45 -

Problems faced during consolidation and future work

- Noticed that the water pipes were blowing off due to hot steam during water

cooling consolidations. So replaced the water pipes with heat resistant pipes

available in department and recovered this problem currently, but has to be

changed by good thermal resistant pipes to fix this problem permanently.

- Time taking for water cooling was also a bit long so advisable to replace the

inlet and out let nozzles with bigger diameter to increase the water flow rate

resulting in less time to cool the platens.

- Insulation to the platens is also advisable to reduce heat loss from surrounding

of platens which will reduce time to reach set temperature and also in good

consolidation results during atmospheric cooling process.

http:/www.insulfrax.com

- Noticed dark boundaries at the edges of the samples after consolidation, this

was a major issue to figure out why it was happening discussed this issue with

advisor, and been advised may be due to bowing effect in the platens at the

pressure applied and heating conditions. Refer to Fig 25 for bowing effect. To

overcome this problem further simulation is required to the platens.

- 46 -

Acknowledgement

Special thanks to Dr Philip Harrison, Materials engineering group, Mechanical

engineering department, University of Glasgow. Who has supported at every stage

and advised when ever needed. Due to his remarkable and new ideas was possible in

successfully completion of this project. Being friendly and always looking after

project progress time to time which was really helpful. Thanks for that dedication

once again.

Also thanks to Mr. David Johnson, Lab in charge, Materials lab, Mechanical

engineering department, University of Glasgow. Who has taken his valuable time for

testing the specimens for investigating of mechanical properties. Who was friendly,

helping nature and hard working, used to resolve problems if any by himself during

testing.

Thanks to Ms Kelly Johnson of Don & Low Ltd who has supplied SRC sheets for

investigations which is really appreciable.

- 47 -

References

1. Don & Low data sheets. pdf

2. http://www.compositesworld.com/ct/issues/2006/April/1278/3

3. Mr Andrew Cochrane report

4. Lankhorst Indutech. ‘reinforced plastics’, p.16, June 2006.

5. O.A. Khonder, X. Yang, N. Usui, H. Hamada, ‘Mechanical properties of textile-inserted PP/PP knitted composites using injection-compression molding’, composites, Vol 37, pp. 2285-2293, 2006.

6. Tang et al. Effects of processing condition on morphology and mechanical

behaviour of PP/PP composites. ICCM-14, San Diego, California, 2003.

7. http://en.wikipedia.org/wiki/Polypropylene

8. http://www.3dchem.com/molecules.asp?ID=331

9. http://www.plastemart.com/upload/literature/selfreinforced.asp

10. http://www.rapra.net/products_and_services/Books/General /General/Recycling_of_Polypropylene.asp

- 48 -

Appendix-1 Thermocouples calibration using glass thermometer and hot water: Thermometer Probe 1 Probe 2 Probe 3 Probe 4 Probe 5

60 59 58 59 59 58 70 68 69 69 68 69 80 79 79 79 79 78 90 89 90 90 89 90 100 98 99 97 98 99

Appendix 2 Water Flow rate readings Water flow rate from Tap: Water measured using glass beaker(500ml) from tap

TRIAL 1 TRIAL 2 meas(ml) Left tap Right Tap L R

200 14.76 14.53 13.95 14.85 300 20.47 20.47 19.84 20.74 400 26.64 27.45 26.28 27.4 500 33.07 33.84 32.76 34.06

Water measured using glass beaker(500ml) at inlet

TRIAL 1 TRIAL 2

meas(ml) Left

tap(TOP) Right

Tap(BOTTOM) L(T) R(B) 200 7.24 7.24 7.11 7.65 300 10.26 10.8 10.48 10.39 400 14.31 14.26 14.44 14.44 500 17.95 17.73 17.68 17.86

Out put of water from the platens:

T(L) B® L R 200 28.75 12.46 28.26 12.64 300 40.14 17.5 40.54 17.77 400 53.95 23.85 54.04 24.03 500 67.18 29.74 67.09 29.88

- 49 -

Appendix 3 Test Samples Consolidation and cooling readings Test Samples @ 145 set, act 140 degrees, 240 x 240mm, 100 br, 30 min in press

W/C At/C Time Temp Time Temp

0 20 0 20 5 35 5 35 10 52 10 52 15 68 15 68 20 83 20 83 25 97 25 97 30 110 30 110 40 131.5 40 131.5 45 142 45 142 48 145 48 145 58 145 58 145 63 145 63 145 73 145 73 145 83 145 83 145 93 145 93 145 98 115 98 140

103 80 103 136 108 60 108 132 113 47 113 128 118 37 118 124 123 33 123 120 128 29 128 116 133 25 133 112 138 21 138 109

143 106 148 103 153 100 158 97 163 95 168 93 173 91 178 89 183 87 188 85 193 83 198 81 203 79 208 77 213 75 218 73 223 71 228 69 233 67 238 65

243 63 248 61 253 59 258 57

- 50 -

2. Test sample @152 set, act 147, 4 lyr, 100br, 30min in press W/C At/C Time Temp Time Temp

0 20 0 20 10 52 10 52 20 83.5 20 83.5 30 110 30 110 40 131.5 40 131.5 50 148 50 148 54 152 54 152 69 152 69 152 79 152 79 152 89 152 89 152 99 152 99 152

104 127 104 147.5 109 102 109 143.5 114 75.5 114 139.5 119 57 119 135.5 124 45 124 131.5 129 39 129 127.5 134 32 134 123.5 139 25 139 119.5 144 21 144 115.5

149 112.5 154 109.5 159 106.5 164 103.5 169 100.5 174 98.5 179 96.5 184 94.5

263 55 268 53 273 51 278 49 283 47 288 45 293 43 298 41 303 39 308 37 313 35 318 33 323 31 328 29 333 27 338 25 343 23 348 21

- 51 -

189 92.5 194 90.5 199 88.5 204 87.5 209 84.5 214 82.5 219 80.5 224 78.5 229 76.5 234 74.5 239 72.5 244 70.5 249 68.5 254 66.5 259 64.5 264 62.5 269 60.5 274 58.5 279 56.5 284 54.5 289 52.5 294 50.5 299 48.5 304 46.5 309 44.5 314 42.5 319 40.5 324 38.5 329 36.5 334 34.5 339 32.5 344 30.5 349 28.5 354 26.5 359 24.5 364 22.5 369 20.5

3. Test Sample @155 degrees,act 150 degrees, 100br, 30min in press


0 20 0 20 5 35 5 35 10 52 10 52 15 68 15 68 20 83 20 83 25 97 25 97 30 110 30 110 40 131.5 40 131.5

- 52 -

50 147.5 50 147.5 56 155 56 155 71 155 71 155 86 155 86 155

101 155 101 155 106 129 106 150.5 111 104 111 145.5 116 86 116 141.5 121 59 121 137.5 126 47.5 126 133.5 131 40 131 129.5 136 34 136 125 141 30.5 141 121 146 27 146 117.5 151 24 151 114.5 156 21 156 111.5

161 108.5 166 105.5 171 102.5 176 100.5 181 98.5 186 96.5 191 94.5 196 92.5 201 90.5 206 88.5 211 86.5 216 84.5 221 82.5 226 80.5 231 78.5 236 76.5 241 74.5 246 72.5 251 70.5 256 68.5 261 66.5 266 64.5 271 62.5 276 60.5 281 58.5 286 56.5 291 54.5 296 52.5 301 50.5 306 48.5 311 46.5 316 44.5 321 42.5 326 40.5 331 38.5 336 36.5

- 53 -

341 34.5 346 32.5 351 30.5 356 28.5 361 26.5 366 24.5 371 22.5 376 20.5

4. Test sample @158 set, act 153 degrees, 100br, 30min in press


0 20 0 20 5 35 5 35 10 52 10 52 15 68 15 68 20 83 20 83 25 97 25 97 30 110 30 110 40 131.5 40 131.5 50 147.5 50 147.5 58 158 58 158 73 158 73 158 83 158 83 158 93 158 93 158

103 158 103 158 123 126.5 108 154 133 72.5 113 150 143 49 118 145.5 153 34.5 123 141.5 163 28 128 137.5 173 22 133 133.5

138 129.5 143 125 148 121 153 117.5 158 114.5 163 111.5 168 108.5 173 105.5 178 102.5 183 100.5 188 98.5 193 96.5 198 94.5 203 92.5 208 90.5 213 88.5 218 86.5

- 54 -

223 84.5 228 82.5 233 80.5 238 78.5 243 76.5 248 74.5 253 72.5 258 70.5 263 68.5 268 66.5 273 64.5 278 62.5 283 60.5 288 58.5 293 56.5 298 54.5 303 52.5 308 50.5 313 48.5 318 46.5 323 44.5 328 42.5 333 40.5 338 38.5 343 36.5 348 34.5 353 32.5 358 30.5 363 28.5 368 26.5 373 24.5 378 22.5 383 20.5

- 55 -

Appendix 4 Maximum Load Graphs For all specimens at all temperatures:

Figures showing Maximum load of specimens

@140 (0C) 0 degree angle At/C top

0

100

200

300

400

500

600

700

0 2 4 6 8 10 12

Extension (mm)

Load

(N) 1

2

3

Maximum

top Load (N)

Specimen 1 588.607788 Specimen 2 567.626953 specimen 3 487.89978

@140 (0C) 0 degree angle At/C middle

0

100

200

300

400

500

600

700

0 1 2 3 4 5 6 7 8

Extension (mm)

Load

(N) 1

2

3

Maximum

middle Load (N)


- 56 -

@140(0C) 0 degree angleAt/C bottom

0

100

200

300

400

500

600

700

800

0 1 2 3 4 5 6 7 8

Extension (mm)

Load

(N) 1

2

3

bottom Maximum

Load (N)

sample 1 262.451172 sample 2 682.067871 sample 3 590.896606

@147 (0C) 0 degrees angle At/C Top

0

100

200

300

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700

0 1 2 3 4 5 6 7

Extension (mm)

Load

(N) 1

2

3

Top Maximum Load (N)


- 57 -

@147 (0C) 0 degrees angle At/C Middle

0

100

200

300

400

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0 1 2 3 4 5 6 7

Extension (mm)

Load

(N) 1

2

3

Middle Maximum

Load (N)

Specimen 1 471.496582 Specimen 2 550.460815 Specimen 3 477.981567

@147 (0C) 0 degrees angle At/C Bottom

0

100

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0 1 2 3 4 5 6 7

Extension (mm)

Load

(N) 1

2

3

Bottom Maximum Load (N)


- 58 -


0

100

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0 1 2 3 4 5 6 7

Extension (mm)

Load

(N) 1

2

3




0

100

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0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3

Middle Maximum

Load (N)


- 59 -


0

100

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0 1 2 3 4 5 6 7

Extension (mm)

Load

(N) 1

2

3




0

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0 1 2 3 4 5 6 7

Extension (mm)

Load

(N) 1

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- 60 -


0

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0 1 2 3 4 5 6 7

Extension (mm)

Load

(N) 1

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3

Middle Maximum

Load (N)



0

100

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300

400

500

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0 1 2 3 4 5 6 7

Extension (mm)

Load

(N) 1

2

3

Bottom Maximum

Load (N)

Specimen 1 560.760498 Specimen 2 531.768799

- 61 -

@140 (0C) 0 degrees angle W/C Top

0100200300400500600700800

0 2 4 6 8 10

Extension (mm)

Load

(N) 1

2

3



@140 (0C) 0 degrees angle W/C Middle

0100200300400500600700800

0 1 2 3 4 5 6 7 8 9

Extension (mm)

Load

(N) 1

2

3

Middle Maximum

Load (N)


- 62 -

@140 (0C) 0 degrees angle W/C Bottom

0100200300400500600700800

0 2 4 6 8 10 12

Extension (mm)

Load

(N) 1

2

3




0

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0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3



- 63 -


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0 1 2 3 4 5 6 7 8

Extension (mm)

Load

(N) 1

2

3

Middle Maximum Load (N)



0

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0 1 2 3 4 5 6 7 8 9

Extension (mm)

Load

(N) 1

2

3

bottom Maximum Load (N)


- 64 -


0

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0 1 2 3 4 5 6 7

Extension (mm)

Load

(N) 1

2

3

top Maximum Load (N)



0

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0 1 2 3 4 5 6 7 8

Extension (mm)

Load

(N) 1

2

3

middle Maximum

Load (N)


- 65 -


0

100

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0 1 2 3 4 5 6 7 8 9

Extension (mm)

Load

(N) 1

2

3

bottom Maximum

Load (N)



0

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0 1 2 3 4 5 6 7 8

Extension (mm)

Load

(N) 1

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3



- 66 -


0

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0 1 2 3 4 5 6 7

Extension (mm)

Load

(N) 1

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3

middle Maximum

Load (N)



0

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0 1 2 3 4 5 6 7

Extension (mm)

Load

(N) 1

2

3

bottom Maximum

Load (N)


- 67 -


01020304050607080

0 2 4 6 8 10 12

Extension (mm)

Load

(N) 1

2

3



@140 (0C) 45 degrees angle At/CMIddle

0102030405060708090

0 1 2 3 4 5 6 7 8

Extension (mm)

Load

(N) 1

2

3

middle Maximum

Load (N)


- 68 -


020406080

100120140160

0 1 2 3 4 5 6 7 8

Extension (mm)

Load

(N) 1

2

3




020406080

100120140160

0 1 2 3 4 5 6

Extension (mm)

LOad

(N) 1

2

3



- 69 -


0102030405060708090

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3

middle Maximum

Load (N)



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0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

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3



- 70 -


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0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

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3



@150 (0C) 45 degreesangle At/C Middle

0

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140

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3

middle Maximum

Load (N)


- 71 -

@ 150 (0C) 45 degrees angle At/C Botttom

0102030405060708090

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3



@153 (0C) 45 degree angle At/C Top

0

20

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140

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3



- 72 -

@ 153 (0C) 45 degree angle At/C Middle

020406080

100120140160

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3

middle Maximum

Load (N)


@ 153 (0C) 45 degree angle At/C Bottom

020406080

100120140160

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3



- 73 -

@140 (0C) 45 degree angle W/C Top

0

20

40

60

80

100

120

140

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3



@140 (0C) 45 degree angle W/C Middle

0

20

40

60

80

100

120

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3

middle Maximum

Load (N)


- 74 -

@ 140 (0C) 45 degree angle W/C Bottom

0

50

100

150

200

250

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3

bottom Maximum

Load (N)



020406080

100120140160

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3



- 75 -


0

20

40

60

80

100

120

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3

middle Maximum

Load (N)


@ 147 (0C) 45 degrees angle W/C Bottom

0

20

40

60

80

100

120

140

0 1 2 3 4 5 6

Extension (mm)

LOad

(N) 1

2

3



- 76 -


020406080

100120140160180

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3



@150 (0C) 45 degrees W/C Middle

0

20

40

60

80

100

120

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3

middle Maximum

Load (N)


- 77 -


0

20

40

60

80

100

120

140

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3

bottom Maximum

Load (N)



0

20

40

60

80

100

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140

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3



- 78 -

@ 153 (0C) 45 degrees angle W/C Middle

0

20

40

60

80

100

120

140

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3

middle Maximum

Load (N)


@ 153 (0C) 45 degrees angle W/C Bottom

020406080

100120140160

0 1 2 3 4 5 6

Extension (mm)

Load

(N) 1

2

3



consolidation of self-reinforcing composites and...

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