In an orthogonal cutting experiment, an $$HSS$$ tool having the following tool signature in the orthogonal reference system $$(ORS)$$ has been used: $$0-10-7-7-10-75-1$$
Given : Width of cut $$=3.6mm;$$
Shear strength of work piece material $$460N/m{m^2};$$
Depth of cut $$=0.25mm;$$
Coefficient of friction at chip tool interface $$=0.7.$$

Shear plane angle (in degrees) for minimum cutting force is

During machining, the wear land $$(h)$$ has been plotted against machining time $$(T)$$ as given in the following figure.

For a critical wear land of $$1.8mm,$$ the cutting tool life (in $$min$$) is

Brittle materials are machined with tools having zero or negative rake angles because it

In an orthogonal cutting test, the following observations were made
Cutting force $$=1200N ;$$ Thrust force $$=500N$$
Tool rake angle $$=zero ;$$ Cutting speed $$=1$$ $$m/s,$$
Depth of cut $$=0.8mm;$$
Chip thickness $$=1.5$$ $$mm$$

Chip speed along the tool rake face will be