Material Technology - May 2014
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.
1(a) Write note on any four:Flame hardening(5 marks) 1(b) Composite materials(5 marks) 1(c) Classify crystal imperfections(5 marks) 1(d) Normalising(5 marks) 1(e) Allotropic forms of iron(5 marks) 1(f) Classfication of engineering materials.(5 marks) 2(a) What is Dislocation?What are the sources of Dislocation?Compare edge and screw Dislocation.(10 marks) 2(b) What is plastic deformation?Discuss how plastic deformation of single crystal takes place by slip mechanism and twinning mechanism(10 marks) 3(a) state Griffth theory of brittle fracture.on its basis,derive an expression for frature stress .State Orrowan's modification.(10 marks) 3(b) How creep test is carried out?Explain Andrade analsyis of creep.(10 marks) 4(a) What is Fatigue limit explain with S-N curve?Explain fatigue testing.(10 marks) 4(b) What is hardenability?Explain jominy End Quench test method to measure hardenability.(10 marks) 5(a) Define 'Alloy'.name different types of alloys.Discuss Hume-Rothery condition of formation of solid solution.(10 marks) 5(b)
Draw Fe-Fe3C Diagram and Explain Eutecoid Eutectic and peritectic transformation in the Fe-Fe3C Diagram.(10 marks) 6(a) Draw a neat time Temperature transformation (TTT)and CCT of 0.8% carbon steel and label all important points and phases.(10 marks) 6(b)
Write short note on:
(i) Nanomaterials,br> (ii)Effect of alloying element on Fe-C diagram.