How we cut metals or hard substance?
Cutting tools are more ancient than fire.Not only they were the survival weapons of prehistoric man but they were the base of our development too. The evolution of cutting tools started from bones and stones to now-a-days metals and advanced materials. What they all have common? They all have to be tougher as well as harder. How does both of the terms are different? Toughness is the force a body survives before cracking and bulk failure. Hardness is surface property.Too much hard means you cannot scratch the surface. An elephant is tougher with a sensitive skin rather than a crocodile which has harder skin.Just an analogy. Getting back to cutting tools.Today we use cutting tools to remove material from a work piece giving it a shape accordingly.The material is removed at very high speed by relative motion between tool and workpiece. And these materials are used for various purposes. Day by day,our world not only demands quantity of a product but also quality. Tou
