Material Science & Metallurgy - Jun 2015
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) What do you mean by co-ordination number? With a neat figure, Co-ordinations number for HCP structures(4 marks) 1 (b) What is Crystal Imperfections? With a neat sketches, explain line defects and surface defects(12 marks) 1 (c) Explain briefly, Factors affecting diffusion.(4 marks) 2 (a) Differentiate between i) Engg. Stress of True stress ii) Engg. Strain and True strain. Derive the relation between Engg. Strain and True Strain(8 marks) 2 (b) Explain with neat sketches, plastic deformation by i) .Slip and ii) Twinning(8 marks) 2 (c) Draw the stress - strain curve for a ductile material and explain the important points on the curve.(4 marks) 3 (a) What do you mean by Type - I, Type-II and Type - III fractures? Explain with neat sketches(6 marks) 3 (b) What is Creep? Explain creep curve,with neat sketch(8 marks) 3 (c) Explain with neat sketches,Typical fatigue stress cycles (Fatigue Loading).(6 marks) 4 (a) Explain with neat sketch, the mechanism of solidification(5 marks) 4 (b) What is Homogeneous Nucleation? With a neat sketch, derive the relation for free energy charge Δ fe (10 marks) 4 (c) Explain Hume-Rothary Rules for formation of solid solutions.(5 marks) 5 (a) Explain briefly the construction of phase diagram using cooling curve, with a neat sketch.(5 marks) 5 (b) Name the different types of phase diagrams. Explain with a neat sketch solid solution phase diagram (Complete solubility).(10 marks) 5 (c) Draw the Iron - Carbon Equilibrium diagram and label all the phases(5 marks) 6 (a) What do you mean by T - T - T curves? Explain with neat sketches, the construction of TTT curves for plain carbon steel(10 marks) 6 (b) Explain with neat sketch, Pack carburizing(5 marks) 6 (c) Explain with neat sketch, Flame Hardening(5 marks) 7 (a) Explain the Composition, Properties and Applications of i) Gray cast iron ii) Malleable cast iron(10 marks) 7 (b) Explain the Composition, Properties and Application of
i) Aluminium - Copper Alloys ii) Aluminium - Zinc Alloys.(10 marks) 8 (a) Define the Composite material. Explain the different types of Matrix Materials and Types of Reinforcements.(10 marks) 8 (b) Explain with a neat sketch, the 'Pultrusion' process for producing FRP's(6 marks) 8 (c) Give the Advantages and Applications of composites(4 marks)