Metal Cutting

1
Metal Cutting
2
Metal Cutting Operations

• Turning

Drilling
Horizontal Milling
Vertical Milling
3
Cutting Tools
http//www.youtube.com/watch?vhRooPJAeK24feature
PlayListp3AFB507B668AF162index4
http//www.youtube.com/watch?vivsigqntxnofeature
PlayListp3AFB507B668AF162index22
Multiple Point Cutter
http//www.youtube.com/watch?vmKxX50OMBd4feature
PlayListp3AFB507B668AF162index33
Single Point Cutter
4
Cutting Force

• Metal Removal Rate vfd
• Cutting Force ?Metal Removal Rate

5
Cutting Mechanics

• Orthogonal Cutting Model
• Reducing the model to two dimensional model.
• Chip thickness ratio, r to / tc, always less
  than 1.
• to d, d being the depth of cut tc is the chip
  thickness.
• ls length of the shear plane

6
Cutting Mechanics
7
Cutting Mechanics

• Forces on chip
• Tool forces Normal force, N Frictional force, F
  ? N ? tan?
• Shear plane forces Shear force, Fs Normal
  force, Fn
• Shear stress on shear plane ? Fs /As As to
  w/sin?
• As Shear plane area.

8
Cutting Mechanics

• F Fc sin? Ft cos?
• F Fc cos? - Ft sin?
• Fs Fc sin ? - Ft co ?
• Fn Fc sin ? Ft cos ?
• Fc cutting force
• Ft thrust force

9
Power Energy

• Power, P Fcv
• Unit power, U
• Specific energy
• Power / Material Removal Rate P / MRR
• Fcv / (vtow)
• Fc / (tow)

10
Power Energy
11
Size Effect Correction
12
Temperature

• Rise in temperature at tool chip interface,
• or, in general