1A. Which equilibrium phase on the Fe-Fe
phase diagram changes to Martensite when cooled quicklyenough?
A. Austenite B. Ferrite C. Bainite D. Cementite
1B. For a tapered cross section metal bar that contracts whencooled, what is the stress status when the part is quenched to roomtemperatures (25 pts)?
A. The edge is in compression and the heavier section is intension B. The edge is in tension and the heavier section is incompression C. No residual stresses will be built in thecomponent
1C. A cylindrial carbon steel ingot is cooled from austenitetemperatures to room temperatures, what is the stress status in theingot (25 pts)?
A. The surface of the ingot is incompression and the center oftheingot is in tension B. The surface of the ingot is in tensionand the center is in compression C. No residual stresses will bebuilt in the component