If the hot steel is cooled rapidly the austenite changes into a new structure called ‘MARTENSITE’. This structure is very fine grained, very hard and magnetic. It is extremely wear-resistant and can cut other metals.
23) Which one of the following structures of steel is obtained due to the drastic cooling from the austenite structure ?
Answer is:
Martensite
Explanation:
Related Heat Treatment MCQ with Answers
Answer is:
Annealing
Explanation:
The annealing process is carried out by heating the steel above the critical range, soaking it for sufficient time to allow the necessary changes to occur, and cooling at a predetermined rate, usually very slowly, within the furnace.
Answer is:
To improve machinability
Explanation:
Purpose of Annealing process is to
- To soften the steel.
- To improve the machinability.
- To increase the ductility.
- To relieve the internal stresses.
- To refine the grain size and to prepare the steel for subsequent heat treatment process.
Answer is: