Material Science & Metallurgy - Dec 2014
Mechanical Engineering (Semester 3)
TOTAL MARKS: 100
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any four from the remaining questions.
(3) Assume data wherever required.
(4) Figures to the right indicate full marks. 1 (a) (i) State the importance of study of "Material Science" and briefly explain engineering requirement of materials.(3 marks) 1 (a) (ii) What are slip bands and slip lines? Draw required sketches. What causes the formation of such bands on a metal surface.(4 marks) 1 (b) Explain and differentiate Edge dislocation and Screw dislocation with neat sketch.(7 marks) 2 (a) What is critical nucleus? In case of crystallization of metals, what is the difference between an embryo and a nucleus. What is the significance of critical radius of a solidifying particle?(7 marks)
Answer any one question from Q2 (b) & Q2 (c)
2 (b) Using Gibb's phase rule, explain unary phase diagram with the help of sketch.(7 marks) 2 (c) What is cooling curve? Explain and differentiate time temperature cooling curve of an alloy of eutectic composition and pure metal.(7 marks)
Answer any two question from Q3 (a), (b) & Q3 (c), (d)
3 (a) Write a short note on: "Iron-iron carbide equilibrium diagram".(7 marks) 3 (b) With the aid of an iron- iron carbide equilibrium diagram show and explain eutectic, peretectic and eutectoid transformation. Also mention the significance of these transformations.(7 marks) 3 (c) State composition, specific properties and applications of Grey Cast Iron.(7 marks) 3 (d) What is phase diagram? Explain Lever rule.(7 marks)
Answer any two question from Q4 (a), (b) & Q4 (c), (b)
4 (a) Explain the steps to obtain the TTT-diagram for eutectoid steel and show on it the cooling curve representing annealing and hardening process.(7 marks) 4 (b) What are the purpose of Alloying ? Give effects of nickel as an alloying element.(7 marks) 4 (c) Describe and compare Austempering and Martempering.(7 marks) 4 (d) Enlist the properties of pure aluminium and mention the composition, properties and application of any one aluminium alloy(7 marks)
Answer any two question from Q5(a), (b) & Q5 (c), (d)
5 (a) What is Powder Metallurgy? Explain the process of Powder Metallurgy.(7 marks) 5 (b) What do you mean by Non-destructive testing? Differentiate destructive and non-destructive testing by stating benefits and limitations.(7 marks) 5 (c) Describe with neat sketch how would you carry out a Jominy harden ability test on a steel sample.(7 marks) 5 (d) Give specific applications of powder metallurgy parts also describe merits and de-merits of powder metallurgy proess.(7 marks)