This is the B.Tech Semester III examination paper for Materials Engineering (KME303).
The exam carries 100 marks and comprehensively covers the structure, properties, phase transformations, heat treatment, failure theories, alloys, and mechanical behaviour of engineering materials.
The paper is designed to test a student’s conceptual understanding, analytical ability, diagram interpretation skills, and application of materials science concepts in real engineering problems.
The question paper is divided into three sections – A, B, and C.
SECTION A – Short Theoretical Questions (20 Marks)
This section contains 10 compulsory questions, each worth 2 marks.
They test fundamental knowledge of:
Unit cell in crystal structures
Ductility vs malleability
Stress intensity factor (fracture mechanics)
Drawing planes using Miller Indices (011), (001)
Gibbs phase rule
Use of phase diagrams
Critical cooling rate in heat treatment
Need for tempering after hardening
Brass vs bronze
Superalloys and examples
These questions check quick recall and basic concept clarity.
SECTION B – Descriptive / Analytical Questions (30 Marks)
Students must attempt any three out of five questions (each 10 marks). Topics include:
Classification of crystal defects with detailed explanation of point defects
Three theories of failure:
Maximum principal stress
Maximum shear stress
Maximum distortion energy
Alloy vs solid solution & Hume–Rothery rules of solid solubility
Heat treatment processes (annealing, normalizing, hardening) explained using Fe–C diagram
Cast iron types: grey, malleable, white, spheroidal — compositions & applications
This section evaluates the ability to explain concepts deeply, compare properties, and interpret diagrams.
SECTION C – Long Answer Numerical / Diagram-Based Questions (50 Marks)
There are five main questions (Q3 to Q7), each with two options. Students must answer one part from each question.
Q3 – Stress–Strain & Elastic Recovery
Stress–strain curve of steel + reason for two yield points + true stress vs engineering stress relation
OR
Numerical based on elastic and plastic deformation and recovery after unloading
Q4 – Fracture & Fatigue
Griffith theory for brittle fracture + critical crack size derivation
OR
Fatigue failure and development of S-N curve using RR Moore test
Q5 – Phase Diagrams
Iron–carbon diagram with all invariant reactions
OR
Lead–tin eutectic phase diagram + calculation of α and β phase fractions at eutectic point
Q6 – Surface Hardening / TTT Diagram
Surface hardening of steel with sketches (carburizing, nitriding, cyaniding etc.)
OR
Method for developing TTT curve + transformations (pearlite, bainite, martensite)
Q7 – Alloying & Special Alloys
Need for alloying steel + effects of elements (Cr, Ni, Mo, V, Mn, Si etc.)
OR
Composition & applications of common engineering alloys:
Monel metal
Muntz metal
Gun metal
Duralumin
Y-alloy
This section tests high-level understanding, phase transformation knowledge, diagrams, and real-world engineering material behaviour.
OVERALL SUMMARY
The Materials Engineering (KME303) question paper thoroughly evaluates:
Crystal structures & defects
Mechanical properties & failure theories
Phase diagrams (Fe-C, Pb-Sn)
Heat treatment processes
Stress–strain behaviour
Fracture & fatigue
Surface hardening
Alloy classification & compositions
Engineering alloys & applications
It combines short conceptual questions, descriptive theoretical explanations, diagram-based questions, and numerical problems, ensuring complete assessment of a student’s understanding of material science.
