Anna University Chennai 2005 B.Tech Mechanical Engineering ENGINEERING MATERIALS & METALLURGY - Question Paper

ENGINEERING MATERIALS & METALLURGY ME 202/205 fourth Sem. May 2k5

Note: part A is compulsory. Attempt any 4 ques. from part B and 2 from part C

part A Marks two every

1.

What is the difference ranging from ceramic and polymer?
compute the number of atoms in FCC structure.
describe Polymorphism.
What do you mean by Recrystallization?
What is Phase Rule?
obtain degree of freedom at triple point.
Draw crystal structure of martensite.
Name 2 non-equilibrium phases of iron-carbon alloy.
describe actual stress.
Why is tempering treatment done after quenching?
part B Marks five every

2. Draw [2 one 1] and (2 two 1) in BCC unit cell.

3 What do you mean by imperfect lattice? How many kinds of crystal defects occur in materials? define them.

4. How does plastic deformation occur? define their mechanism. What is difference ranging from thermal and mechanical twins?

5. obtain the line energy of dislocation in BCC structure. The shear modulus of material is 80.2 GN/m2 and lattice constant is 2.87 Å.

6. elaborate various equilibrium phase reactions that occur in phase diagram? define them. Draw a peritectic phase diagram and mark all points and lines.

part C Marks 10 every
7. (a) elaborate annealing and normalizing treatments? discuss why hypereutectoid steel is not provided full annealing treatment?
(b) What is T-T-T diagram? define how it is found. Mention its importance.

8. Draw a hypothetical phase diagram A-B with the help of subsequent data:
(a) Melting point of A = 1100 oC
(b) Melting point of B = 1300 oC
(c) Eutectic reaction occurs at 1000 oC at 40% B composition.
(d) maximum solubility of B in A and A in B at eutectic temperature in 10% and 5% respectively which drops down to zero at 0 oC.

Mark every line and area. How the structure of alloy will change if alloy containing 10% B composition is cooled from liquid state?
9.. Write short notes on any 2 of the following:
(a) surface hardening processes
(b) Ferrite stabilizer in steels.
(c) Hardenability and its measurement

Earning:   Approval pending.