Question

What is the relation of solubility and temperature for an age-hardening alloy?

(a) Increases with decrease in temperature

(b) Decreases with decrease in temperature

(c) Increases irrespective of temperature

(d) No change due to temperature

I got this question at a job interview.

My doubt stems from Metal Spraying and Hard Facing, Age Hardening topic in division Wear of Metals, Mechanical Properties and Testing of Engineering Material & Metallurgy

Answer 1

Right option is (b) Decreases with decrease in temperature

To elaborate: The most important requirement of an age-hardening alloy is that its solubility must decrease as the temperature decreases. This gives a supersaturated solid solution necessary for age-hardening of alloys.