Engineering Questions with Answers - Multiple Choice Questions
Manufacturing Processes – Annealing – 12
1 - Question
In thermal cycling stage of spheroidised annealing transforms _____ to ______
a) austenite to perlite
b) cementite to carbide
c) cementite from perlite to spheroidal
d) cementite from ferrite to spheroidal
View Answer
Explanation: In this stage, the thermal cycling in the narrow temperature range around lower critical temperature transforms cementite lamellae from pearlite to spheroidal. During heating above lower critical temperature, cementite or carbides try to dissolve and during cooling they try to re-form. This repeated action spheroidises the carbide particles.