Q. The process of production of articles having a soft ductile interior and a very hard surface, is known as (Solved)
1. Hardening
2. Hardening and tempering
3. Case hardening
4. Hardening and annealing
5. None of the above
- c. Case hardening
1. Hardening
2. Hardening and tempering
3. Case hardening
4. Hardening and annealing
5. None of the above