# JNTU PAPERS,B-Tech,I- Semester,Physical Metallurgy, November 2008

JNTU PAPERS

JNTU,B.Tech,I- Semester, Physical Metallurgy, November 2008

(Metallurgy & Material Technology)

SET-1

1. (a) Name various methods of illumination in metallurgical microscope and briefly

explain each one of them.

(b) What is conical stop illumination? Discuss its features.

2. (a) What is coordination number? Discuss with suitable examples.

(b) Prove that the FCC metals are more closely packed than BCC metals.

3. (a) What are the different types of solid solutions. Explain interstitial solid solution with suitable examples.

(b) Discuss in detail the necessity of alloying and explain the same with four specific examples.

4. (a) Describe how the liquidus and solidus of a binary isomorpous phase diagram can be determined Experimentally.

(b) Write the Equation of Gibb’s phase rule. Define and Explain each of the terms

in the equation.

5. (a) Write note on order ? disorder transformation.

(b) Explain the composition, properties & uses of

i. Alpha brass

ii. Beryllium copper

iii. Cupronickels

6. (a) Calculate the relative amounts of the structural constituents present in furnace

cooled steels & cast irons, containing

i. 0.3%C

ii. 0.6% carbon

iii. 1.2%C

iv. 4.3%C

(b) What is critical temperature? Describe various critical temperatures you will

come across in the Fe – Fe3 C diagram.

7. (a) Compare and contrast the structural features of pearlite with that of Bainite.

(b) “Steel is made hard by Quenching”. State at least three conditions which must be fulfilled to justify the above statement.

8. (a) ‘In a TTT curve the incubation period is initially large (at =7000C), which

decreases (as the amount of under cooling increases) to a minimum at the nose

of the curve and then increases’. Justify the correctness/in correctness of the above statement. Give the necessary reasons

(b) CCT curve of eutectoid steel is displaced towards right and lowered as com-

pared to its TTT curves. Explain, why?