Metals are tougher than ceramics Which of the following is N

Metals are tougher than ceramics. Which of the following is NOT true? Plastic deformation occurs at the crack tip in ductile metals Only elastic deformation occurs in brittle ceramics Energy is dissipated by plastic deformation in metals The surface energy is metals is very high Which of the following is NOT good for fatigue life? Increasing the strength of the surface by carburizing Producing a compressive residual stress on the surface by shot-peening Ensuring key ways and changes in cross section are sharp Reducing the amount of inclusions in the metal

Solution

>> In Ductile Metals, Plastic Deformation occurs throughout the whole body, not just on the tip of ductile metals.

So, Option a is not true...

>> By Ensuring Sharp Key Ways, Stress Concentration will increase at these points due to sharp change in cross section, thus reducing the Fatigue Life

So, Ensuring Keyways and changes in cross section are sharp, is not good for fatigue life