Question

Austempering is the heat treatment process used to obtain:

• A. Low hardness
• B. High toughness
• C. High hardness
• D. High ductility

Hint:

Austempering produces bainite, which is harder and stronger than pearlite and offers less distortion than martensite.

Answer 1

The Correct Option is C

Austempering is a heat treatment process mainly applied to ferrous metals, especially steels and ductile irons.
The process involves heating the metal to the austenitizing temperature, then rapidly cooling it in a salt bath held at a temperature where bainite, not martensite, forms.
This results in a bainitic microstructure, which provides improved mechanical properties.
The bainitic structure obtained through austempering has high hardness and strength compared to other structures like pearlite or ferrite.
This process is often preferred where high hardness and better dimensional stability are required.