Material Technology - Dec 2015

Mechanical Engineering (Semester 4)

TOTAL MARKS: 80
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Assume data if required.
(4) Figures to the right indicate full marks.

Write note on any four:

1 (a) Baushinger's effect related to fatigue of metal.(4 marks) 1 (b) Creep Test(4 marks) 1 (c) Effect of Alloy on TTT diagram(4 marks) 1 (d) Critical resolved shear stress(4 marks) 1 (e) Crystal Imperfection(4 marks) 2 (a) What do you mean by Composite Materials? Explain their properties and practical applications.(10 marks) 2 (b) What is Fatigue? Explain fatigue testing in detail.(10 marks) 3 (a) Draw Fe-Fe₃C Diagram and Explain cooling of 1.0% C alloy in the Fe-Fe₃C Diagram.(10 marks) 3 (b) Explain Flame Hardening and Induction Hardening.(10 marks) 4 (a) Draw and explain Time Temperature Transformation (TTT) diagrams of 0.8%C alloy.(10 marks) 4 (b) Derive an expression for Griffith theory of brittle fracture.(10 marks) 5 (a) What is plastic deformation? Distinguish between slip and twin mechanism of plastic deformation.(10 marks) 5 (b) What is case hardening? Explain carburising in detail.(10 marks)

Write short note on any four:

6 (a) Dislocation Jog and Kink.(4 marks) 6 (b) Austempering(4 marks) 6 (c) Bain's distortion model for martensitic transformation.(4 marks) 6 (d) Engineering Materials.(4 marks) 6 (e) Annealing(4 marks)