The following data are obtained during orthogonal machining with Merchants theory.

Ultimate shear strength of work material = 600 MPa,
Rake angle of the tool $=6^{\circ }$,
Coefficient of friction at chip tool interface $=0.2$,
Feed and depth of cut = 0.2 mm/rev and 3 mm respectively. Taylor's tool life equation is $V.T^{0.4}=100$.

The power required during machining operation is

Q. The following data are obtained during orthogonal machining with Merchants theory.

Ultimate shear strength of work material = 600 MPa,
Rake angle of the tool $=6^{\circ }$,
Coefficient of friction at chip tool interface $=0.2$,
Feed and depth of cut = 0.2 mm/rev and 3 mm respectively. Taylor's tool life equation is $V.T^{0.4}=100$.

What is the Optimum cutting velocity during machining if machine hour rate is Rs. 75 and cost of regrinding the tool one time is Rs. 15?

Q. In an orthogonal machining with a tool of 9° orthogonal rake angle, the uncut chip thickness is 0.2 mm. The chip thickness fluctuates between 0.25 mm and 0.4 mm. The ratio of the maximum shear angle to the minimum shear angle during machining is

Q. In the turning experiment, a 50 mm diameter bar is turned using a tool having a rake angle $6^{\circ }$ with orthogonal machining operation at a cutting speed of 40 m/min, chip flow velocity is 20 m/min. The feed and depth of cut are 0.24 mm/rev and 1.8 mm respectively. $F_c$ is observed as 800 N and $F_t$ as 290 N. The shear stress induced in the work material during machining operation is

Q. In a turning operation with orthogonal machining the spindle rotates at 270 rpm and the tool is fed at a rate of 0.3 mm per revolution. The depth of cut is 0.5 mm. The rake angle is ${10}^{\circ }$ and the coefficient of friction at the tool chip interface to be 0.5317. What is the value of chip thickness?

Q.

Common Data:
A cylinder is turned on a lathe with orthogonal machining principle. Spindle rotates at $200rpm$. The axial feed rate is $0.25mm$ per revolution. Depth of cut is $0.4mm$ The rake angle is ${10}^o$. In the analysis it is found that the shear angle is ${27.75}^o$.

In the above problem, the coefficient of friction at the chip tool interface obtained using Earnest and Merchant theory is