Given the Fe-C phase diagram and answer question 1 - 5

1. (5 pts) What is the eutectic composition of carbon for the Iron-Carbon phase diagram?

2. (5 pts) Martensite steels are the hardest and strongest, yet most brittle

a) True

b) False

3. Consider austenite containing 0.65 wt% C, cooled to just below 727C. Answer the following 3 questions:

(1) (5 pts) What is the proeutectoid phase?

a) Ferrite

b) Cementite

(2) (10 pts) What is the weight fraction of total ferrite and cementite?

(3) (10 pts) what is the weight fraction of pearlite and the proeutectoid phase?

4. Consider the austenite containing 1.0 wt% C, cooled to below 727C.

(1) (10 pts) What is the weight fraction of total cementite?

(2) (10 pts) what is the weight fraction of proeutectoid phase?

5. (10 pts) Schematic room-temperature microstructures for three ion-carbon alloys are as follows. Rank these microstructures (by letter) form the hardest to the softest.

(B) (C)