thermal aspects of metal machining
DESCRIPTION
this presentation tries to explain the various heat zones that are developed during the metal cutting process. furthermore, how much heat is dissipated from the various zones. lastly the possible methods of temperature reduction in brief.TRANSCRIPT
![Page 1: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/1.jpg)
Thermal aspects of metal machining
Presented by : Lav Kumar 106073 Vishal Chaturani 114089
![Page 2: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/2.jpg)
Machining or metal cutting
Objective of metal cutting:• Removing unwanted material• Cutting/chipping/machining/metal
cutting• To get desired
o Shapeo Sizeo Surface finish
![Page 3: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/3.jpg)
Essentials of MetalCutting Operation1.Machine Tool 3.Method2.Cutting Tool 4. Operator
![Page 4: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/4.jpg)
Mechanism of MetalCutting
Tool & Workpiece interaction: given a depth of cut and relative of motion between tool and workpiece results in chipping.
![Page 5: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/5.jpg)
Thermal Aspect Of Machining
• The power consumed in machining is largely converted into heat near the cutting edge of the tool.
• This causes the temperature of the tool, chip and workpiece to rise.
• This can influence the properties of the work material being machined, as well as the effective life of the cutting tool.
![Page 6: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/6.jpg)
Distribution of Heat Plastic deformation by shearing in the primary shear
zone Plastic deformation by shearing and � friction on the
cutting face � Friction between chip and tool on the tool flank
![Page 7: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/7.jpg)
PRIMARY ZONE• Also known as shear zone.• Maximum heat is generated due to plastic
deformaion of metal.• Since the process is continuous and rapid
process,80-85% heat is generated from this zone.
![Page 8: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/8.jpg)
SECONDARY ZONE• It is also called a friction zone.• As the chip moves along the tool face under great
pressure being resisted by the friction• Heat is generated due to friction between moving
chip on rake face of tool.• 15-20% heat is generated in this zone.
![Page 9: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/9.jpg)
Tertiary zone• It is the work tool contact zone.• Burnishing action is the cause of heat
generation.• Rarely present , if present then 1-3% of
heat generation occurs and occurs due to built up edge formations.
![Page 10: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/10.jpg)
Disadvantages of heat generation
• Affects the wear of the cutting tool.• Can induce thermal damage to the
machined surface• Causes dimensional errors in the
machined surface
![Page 11: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/11.jpg)
Heat dissipation
The temperature in metal cutting can be reduced by:
Application of cutting fluids .Application of coolants. Change in the cutting conditions by reduction
of cutting speed and/or feed; Selection of proper cutting tool geometry
(positive tool orthogonal rake angle).
![Page 12: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/12.jpg)
Simplest way of temperature reduction
simplest way to reduce the cutting temperature is to reduce the cutting speed and/or feed.
Cutting temperature T as a function of cutting speed V, feed f, and depth of cut d
![Page 13: Thermal Aspects of Metal Machining](https://reader033.vdocument.in/reader033/viewer/2022061317/554a53a8b4c9054b328b499b/html5/thumbnails/13.jpg)
THANK YOU