SS#_________________________

Grade_________________/100

Metal 259 - Fall-1995 - Exam 1

Par time - 7 min. (Time required to read questions, think a little, and write answers)

1. Put your social security no. on the line above now.

2. For the questions below, only short answers are required.....usually only a few words. Thus, only a small amount of space in each has been left for your answer; only answers placed in the space provided will be considered. Diagrams and drawings, where appropriate, are welcome. Many hours will be required to grade this exam; you can help us (read as "get your graded exam back sooner") by writing clearly and as succinctly as possible.

3. (10) List three ways in which the tensile strength of steels can be increased.

a.

b.

c.

4. (10) Explain the AISI/SAE steel designation code.

5. (10) What is the basis for the Aluminum Association classification system (discussed in class) for wrought aluminum alloys?

6. (10) Suppose we have an Al-4%Cu alloy. Slow cooling and rapid cooling (quenching) of this alloy produce materials with different structures and properties.

a. What fundamental atomic process is prevented from taking place in rapid cooling?

b. Rapid cooling produces a structure with ___________ phase(s) and slow cooling

produces a structure with ___________ phase(s). 

7. (10) Why are solid solution alloys harder than the corresponding non-alloyed pure metal?

8. (10) A brass alloy is to be used in an annealed condition. Since the alloy will not be work hardened and cannot be precipitation hardened, what can be done to the grain structure to strengthen the material?

9. (10) Compare the ductilities of metallic, ceramic, and polymeric materials.

10. (10) Show below how the fracture energy upon impact varies with test temperature. Mark axes.

11. (20) Define:

a. Yield strength

b. Hardness

c. Dislocation

d. Slip plane

e. Phase