GTU BE 8th Semester 182102 Selection of Materials and Failure Analysis Summer 2018 Question Paper

1
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE – SEMESTER ?VIII (old) – EXAMINATION ? SUMMER 2018
Subject Code: 182102 Date:30/04/2018
Subject Name: Selection of Materials and Failure Analysis
Time: 10:30 AM to 01:00 PM Total Marks: 70
Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 (a) Explain the role of material engineer for selection of materials in Design
Synthesis.
07
(b) What is a failure analysis? What are the basic steps involved in performing a
failure analysis?
07

Q.2 (a) Explain how does availability of material& the cost of material affects the
selection process ? Give suitable example.
07
(b) Define stiffness & explain the criteria for selecting material for stiffness. 07
OR
(b) Discussed the case study of selecting the material based on the mechanical
properties of strength, toughness & fatigue.
07

Q.3 (a) Define hydrogen embrittlement of steel. Explain the mechanism of hydrogen
induced cracking in the steels.
07
(b) Discuss the case study of failure of auto component ( like crank pin , gear,
crank bolt, etc.)07
OR
Q.3 (a) Explain macro & micro fracture features by drawing neat sketch in the
following failures 1. Ductile fracture 2. Brittle fracture.
07
(b) Discuss about gear materials. 07

Q.4 (a) Explain macro and micro features of Ductile fracture. 07
(b) Explain three stages of fatigue failure. Differentiate between striations and
beach marks
07
OR
Q.4 (a) Discuss briefly on Material selection for wear resistance. 07
(b) Explain Creep mechanism. On which factors Creep resistance of material
depends? Describe various materials used for Creep resistance.
07

Q.5 (a) Define Toughness. How toughness plays important role in material selection 07
(b) Explain relationship between material selection and material processing. 07
OR
Q.5 (a) Short note on corrosion fatigue and contact fatigue. 07
(b) Define the surface durability. What are the basic criteria for selection of
material for corrosion & wear resistance applications?
07
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