ferrous powder production
DESCRIPTION
Ferrous Powder ProductionTRANSCRIPT
Ferrous Powder production
Mahesh Nipanikar – Höganäs India Pvt :Ltd
Metal Powder Production
● Powder Production:
– Shape
– Particle size
– Size distribution
● Depends on powder production method
Production of Iron Powders
Powder Production
Water-atomisation process – Majorly used
process. ( Plain powders , low alloy powders ,
stainless steels and tool steels)
Sponge iron process – Solid state reduction
of iron ore ( Majorly Fe3O4)
Alloying methods - Premix , organic
bonded mix.
Brazil Belgium India
Japan
China
United Kingdom Sweden Höganäs Sweden Halmstad
North America
Stony Creek
North America
Niagara Falls
North America
SCM
Johnstown
Production Centres
Sponge iron
- Höganäs
Atomisation
-Halmstad
-Stony Creek
-India
-Brazil
High Alloy
-Belgium
-SCM Johnstown
-United Kingdom
Powder production in Sweden
Halmstad Atomising plant
Höganäs Sponge Iron plant
Powder plant
Distaloy plant
Astaloy plant
Customer mixes
Iron powders
Examples:
ASC100.29
ABC100.30
AHC100.29
Examples:
NC100.24
SC100.26
MH80.23
AHC 100.29
Mesh Size
Apparent density (g/cc)
Water-atomising process
1. Selected scrap
2. Arc furnace
3. Liquid steel
4. Injection
5. Atomising
6. Dewatering
7. Drying
8. Magnetic separation
9. Screening
10. Equalising
11. Transportation to Höganäs
A. Tundish
B. Steel stream
C. High pressure water
D. Nozzle
E. Atomised iron powder
Water-atomising process
1. Selected scrap
2. Arc furnace
3. Liquid steel
4. Injectionn powder
Water-atomising process
5. Atomising
1.ected scrap
2. Arc furnace
Liquid steel
4. Injection
A. Tundish
B. Steel stream
C. High pressure water
D. Nozzle
E. Atomised iron powder
● Variables in Atomization
Process:
– Superheat degree of molten
metal.
– Angle of injection of water
– Nozzle size.
– Metal to water ratio
– Water pressure.
Water-atomising process
1. Selected scrap
2. Arc furnace
3. Liquid steel
4. Injection
5. Atomising
6. Dewatering
7. Drying
8. Magnetic separation
9. Screening
10. Equalising
11. Transportation to Höganäs
h pressure water
Atomised iron powders
Examples:
ASC100.29
ABC100.30
AHC100.29
Sponge iron process 1. Reduction mix of coke breeze and limestone
2. Iron ore
3. Drying
4. Crushing
5. Screening
6. Magnetic separation
7. Charging in ceramic tubes
8. Reduction in tunnel kilns, approximately 1200C
9. Discharging
10. Coarse crushing
11. Storage in silos
12. Crushing
13. Magnetic separation
14. Grinding and screening
15. Annealing in belt furnace, 800-900C
16. Equalising
17. Automatic packing
18. Iron ore
19. Reduction mix
20. Control room
Sponge iron process
1. Reduction mix of coke breeze and limestone
2. Iron ore
3. Drying
4. Crushing
5. Screening
6. Magnetic separation
7. Charging in ceramic tubes
8. Reduction in tunnel kilns, approximately 1200C
9.
Sponge iron process
1. Reduction mix of coke breeze and limestone
2. Iron
7. Charging in ceramic tubes
8. belt furnace, 800-900C. Automatic packing
18. Iron ore
19. Reduction mix
20. Control room
Sponge iron process
1. Reduction mix of coke breeze and limestone
2. Iron ore
3. Drying
4in ceramic tubes
8. Reduction in tunnel kilns, approximately 1200C
9. Discharging
Sponge iron process
1. Reduction mix of coke breeze and limestone
2. Iron ore
3. Drying
10. Coarse crushing
11. Storage in silos
12. Crushing
13. Magnetic separation
14. Grinding and screening
15. Annealing in belt furnace, 800-900C
16. Equalising
17. Automatic packing
18. Iron ore
19. Reduction mix
20. Control room
Sponge iron process
1. Reduction mix of coke breeze and limestone
2. Iron ore
3. Drying
4and screening
15. Annealing in belt furnace, 800-900C
16. Equalising
17. Automatic packing
Sponge iron powders
Examples:
NC100.24
SC100.26
MH80.23
Sponge Vs Atomized iron Powders
Mahesh Nipanikar 19 |
Compressibility
5.6
5.8
6.0
6.2
6.4
6.6
6.8
7.0
7.2
7.4
7.6
200 300 400 500 600 700 800 900
Compating pressure (MPa)
Green
den
sity
(g
/cm
3)
ABC100.30
ASC100.29
AHC100.29
SC100.26
NC100.24
MH80.23
Lubricated die
Sponge Vs Atomized iron Powders
Green strength
5
10
15
20
25
30
35
40
200 300 400 500 600 700 800 900
Compating pressure (MPa)
Green
str
en
gth
(M
Pa
)
MH80.23
NC100.24
SC100.26
ABC100.30
ASC100.29
AHC100.29
0.6% Kenolube
Alloying methods
PRE-ALLOYED ASTALOY
DIFFUSION ALLOYED DISTALOY
PRE-MIXED ORGANIC BONDED STARMIX™
Alloying methods Pre-alloyed
Atomization
Advantages:
•No segregation of alloying
elements
•Homogeneous microstructure
Disadvantages:
•Hard to make alloying changes
Pre-alloyed powders- Astaloys
Powder grade Alloying elements Properties
Astaloy Mo 1,5% Mo
High compressibility with
optimal hardenability-->
surface hardened components
Astaloy A 1,9% Ni, 0,5% Mo, 0,25% MnPrimarily for powder forging
Good hardenability
Astaloy 85 Mo 0,85% MoAdvantages as Astaloy Mo,
but less hardenability
Astaloy CrM 3% Cr, 0,5% Mo
Excellent hardenability, high
strength and hardness after
sintering
Alloying methods - Diffusion alloyed
Advantages:
•Higher compressibility than a
pre-alloyed with same
composition
•Low segregation of alloying
elements
Disadvantages:
•Fixed composition
+
Sponge powder Atomised powder
Cu, Ni, Mo Cu, Ni, Mo
+
Mixing
Diffusion alloyed powders
Powder grade Base powder Alloying elements Properties
Distaloy SA SC100.26 1.75% Ni, 1.5% Cu and 0.5% Mo High green strength
Distaloy AB ASC100.29 " High compressibility
Distaloy SE SC100.26 4% Ni, 1.5% Cu and 0.5% Mo High green strength
Distaloy AE ASC100.29 " High compressibility
Distaloy DC-1
(Dimensional control)Astaloy Mo 2.1% Ni (and 1.5% Mo) No DC change with density
Distaloy DH-1
(Direct hardening)Astaloy Mo 2% Cu (and 1.5% Mo) High hardenability
Distaloy HP-1
(High performance)Astaloy Mo 4% Ni, 2% Cu (and 1.5% Mo) Highest mechanical properties
Compressibility
Chemical composition
1,75 % Ni
1,5 % Cu
0,5 % Mo
Alloying methods
PRE-MIXED ORGANIC BONDED STARMIX™
•Easy to change composition
•Segregation
•Product consistency
•Better flow compared to Premix
•Low dusting
•Close to 100% bonding of graphite
Alloying methods
PRE-MIXED ORGANIC BONDED STARMIX™
0,15
0,20
0,25
0,30
0,35
0,20 0,30 0,40 0,50
Carbon content
Dim
en
sio
na
l c
ha
ng
e
0,15
0,20
0,25
0,30
0,35
0,20 0,30 0,40 0,50
Carbon content
Dim
en
sio
na
l c
ha
ng
e