Question

Which of the following groups of alloying elements stabilize austenite?

(a) Ni, Mn, Cu, and Co

(b) Cr, W, Mo, V, and Si

(c) Cr, W, Ti, Mo, Nb, V, and Mn

(d) Co, Al, and Ni

The question was asked in an interview for internship.

Asked question is from Alloy Steels in section Diffusion in Solids & Ferrous Materials of Engineering Material & Metallurgy

Answer 1

Correct answer is (a) Ni, Mn, Cu, and Co

Easiest explanation: The alloying elements such as Ni, Mn, Cu, and Co have a tendency to alleviate austenite, whereas Cr, W, Mo, V, and Si tend to stabilize ferrites. Alloying elements such as Cr, W, Ti, Mo, Nb, V, and Mn tend to form carbides. Other elements like Co, Al, and Ni help to weaken carbides and thereby form graphite.