Minimum Shear Strain and Strain Rate in Chip Formation

Q. Minimum shear strain in orthogonal turning with a cutting tool of zero rake angle is

1. $0.0$
2. $0.5$
3. $1.0$
4. $2.0$

Q. During orthogonal metal cutting process, the following data is obtained:
Rake angle = 12°
Chip thickness ratio = 0.5
Undeformed thickness = 0.7 mm
Cutting speed = 2.4 m/s
If the mean thickness of primary shear zone is 25 microns, then shear strain rate ($in{s}^{-1}$) during the process is

1. 4.9 × ${10}^4$
2. 0.98 × ${10}^4$
3. 9.8 × ${10}^4$
4. 0.49 × ${10}^4$

Q. A single point cutting tool with ${12}^o$ rake angle is used for orthogonal machining of a ductile material. The shear plane angle for the theoretically minimum possible shear strain to occur

1. $51$
2. $45$
3. $30$
4. None of these

Q. Details pertaining to an orthogonal metal cutting process are given below:
Chip thickness ratio $0.4$
Undeformed thickness $0.6mm$
Rake angle $+{10}^o$
Cutting speed $2.5m/s$
Mean thickenss of primary shear zone $25$ microns
The shear strain rate in $s^{-1}$ during the process is

1. $0.1781\times {10}^5$
2. $0.7754\times {10}^5$
3. $1.0104\times {10}^5$
4. $4.397\times {10}^5$