B.E. (fourth semester) EXAMINATION, Nov-Dec, 2007
(Mechanical Engg. Branch)
(MATERIAL SCIENCE AND ENGINEERING MATERIALS)
Note: Attempt any five questions. All question carry equal marks.
1. (a) What are refectory materials ? Differentiate between acidic and basic refectories.
(b) Draw a (110) and a (111) plan inside the unit cell of cubic crystal. Determine the miller indices of
the direction that is common in both in these plans.
2. (a) What is Van der Waal’s cooling? Enumerate with examples.
(b) Explain why a covalent bond is directional while ionic an metallic bonds are non-directional.
3. (a) Draw a typical ‘creep test’ curve, Showing different stage of elongation for a long time high
Temperature creep test. State how the information is helpful to designer?
(b) Discuss with example the ductile and brittle fracture.
4. (a) Explain the difference between slipping and twinning . How does twinning occur in metals?
(b) Discuss the effect of imperfection on metal properties.
5. (a) Explain Gibbs’ phase rule in detail as applied equilibrium diagram .Define the terms space lattice ,
crystal symmetry, eutectic and eutectoid.
(b) Explain with examples, the cooling from liquid to solid state of a pertitectic transformation.
6. (a) What is TTT curve? Why should the TTT curve for eutectic steel be different from that of alloy
(b) What are the objectives of heat treatment? Describe annealing. its types and advantages.
7. (a) Differentiate between the hypoeutectic and hypereutectic cast irons.
(b) Differentiate between the gray cast iron and white cast iron.
8. (a) Give composition and uses of the following :
(i) Duralumin (ii) Y-alloys
(b) Discuss briefly the differentiate polymerization mechanisms.