Question

Increase of hardness of an alloy with an increase in time is known as ________

(a) Age hardening

(b) Solution hardening

(c) Dispersion hardening

(d) Phase transformation hardening

I have been asked this question in an interview.

The query is from Metal Spraying and Hard Facing, Age Hardening in division Wear of Metals, Mechanical Properties and Testing of Engineering Material & Metallurgy

Answer 1

Right answer is (a) Age hardening

To elaborate: The strengthening of an alloy resulting from the precipitation of a finely dispersed second phase from a supersaturated solid solution is called age hardening. The finely dispersed second phase precipitates with age. This type of hardening is known as age hardening.