Question

The process of increasing strength of a material by changing grain size known as __________

(a) Grain boundary strengthening

(b) Work hardening

(c) Solid solution hardening

(d) Precipitation hardening

The question was posed to me in class test.

The question is from Plastic Deformation in chapter Plastic Deformation and Creep in Crystalline Materials, Elastic, Anelastic and Viscoelastic Behaviour of Engineering Material & Metallurgy

Answer 1

Correct choice is (a) Grain boundary strengthening

The best explanation: Grain-boundary strengthening is the technique of increasing the strength of materials by changing their average crystallite size. This is otherwise known as Hall-Petch method. The Hall-Petch constant is written in the form of MN m^-3/2.