A 0.20 wt% carbon steel gear was pack carburized and carbon concentration at the surface was increased to 0.8wt%, and subsequently heated and held in the austenitic temperature range until complete transformation to austenite occurred. The gear was quenched in water; how would this treatment affect the following properties: (3)
a. Strength at the surface:
b. Hardness at the core:
c. The most probable microstructure/phase at the surface (identify):