In an orthogonal machining operation , the tool life obtained is $$10min$$ at a cutting speed of $$10m/min,$$ while at $$75m/min$$ cutting speed, the tool life is $$30min$$. The value of index (n) in the Taylor's tool life equation is

Diamond cutting tools are not recommended for machining of ferrous metals due to

Using direct extrusion process, a round billet of $$100$$ $$mm$$ length and $$50mm$$ diameter is extruded. Considering an ideal deformation process (no friction and no redundant work), extrusion ratio $$4$$ and average flow stress of material $$300$$ $$MPa,$$ the pressure $$(MPa)$$ on the $$ram$$ will be

A disc of $$200$$ $$mm$$ diameter is blanked from a strip of an aluminium alloy of thickness $$3.2$$ $$mm.$$ The material shear strength to fracture is $$150$$ $$MPa.$$ The blanking force (in $$kN$$) is