2025 question paper
Engineering Materials
28 questions
Q1a. Choose the correct option: Which crystal structure has the highest packing factor and 12 slip systems, making metals with this structure highly ductile? (i) Body-centered cubic (BCC) (ii) Face-centered cubic (FCC) (iii) Hexagonal close-packed (HCP) (iv) Simple cubic20252m
Module 1: Crystal Structure
View this question on its own page →Choose the correct option:
Which crystal structure has the highest packing factor and 12 slip systems, making metals with this structure highly ductile?
(i) Body-centered cubic (BCC)
(ii) Face-centered cubic (FCC)
(iii) Hexagonal close-packed (HCP)
(iv) Simple cubicQ1b. Choose the correct option: The critical resolved shear stress (CRSS) is defined as: (i) The tensile stress required for dislocation motion (ii) The shear stress resolved on the most favorable slip system required to initiate slip (iii) The maximum shear stress in a crystal regardless of orientation (iv) The stress needed to create new dislocations20252m
Module 1: Crystal Structure
View this question on its own page →Choose the correct option:
The critical resolved shear stress (CRSS) is defined as:
(i) The tensile stress required for dislocation motion
(ii) The shear stress resolved on the most favorable slip system required to initiate slip
(iii) The maximum shear stress in a crystal regardless of orientation
(iv) The stress needed to create new dislocationsQ1c. Choose the correct option: Which factor most strongly governs whether a substitutional solid solution forms between metals A and B? (i) Large electronegativity difference between A and B (ii) Similar atomic radii and crystal structures with high mutual solubility (iii) Presence of small interstitial atoms like C or N (iv) High melting point of the solvent metal alone20252m
Module 2: Alloys and Phase Diagrams
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Which factor most strongly governs whether a substitutional solid solution forms between metals A and B?
(i) Large electronegativity difference between A and B
(ii) Similar atomic radii and crystal structures with high mutual solubility
(iii) Presence of small interstitial atoms like C or N
(iv) High melting point of the solvent metal aloneQ1d. Choose the correct option: The eutectic reaction in a binary alloy system is best described as: (i) Liquid \rightarrow Solid 1 (ii) Liquid \rightarrow Solid 1 + Solid 2 (iii) Solid 1 \rightarrow Solid 2 + Solid 3 (iv) Liquid + Solid 1 \rightarrow Solid 220252m
Module 2: Alloys and Phase Diagrams
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The eutectic reaction in a binary alloy system is best described as:
(i) Liquid Solid 1
(ii) Liquid Solid 1 + Solid 2
(iii) Solid 1 Solid 2 + Solid 3
(iv) Liquid + Solid 1 Solid 2Q1e. Choose the correct option: In the Fe-Fe_3C equilibrium diagram, ledeburite is: (i) A mixture of ferrite and austenite (ii) A single-phase austenitic structure (iii) Pure cementite (iv) A eutectic mixture of austenite and cementite20252m
Module 2: Alloys and Phase Diagrams
View this question on its own page →Choose the correct option:
In the Fe-FeC equilibrium diagram, ledeburite is:
(i) A mixture of ferrite and austenite
(ii) A single-phase austenitic structure
(iii) Pure cementite
(iv) A eutectic mixture of austenite and cementiteQ1f. Choose the correct option: In a standard tensile test on a ductile metal, Young's modulus is obtained from: (i) The entire stress-strain curve up to fracture (ii) The slope of the initial linear portion of the engineering stress-strain curve (iii) The maximum load divided by original area (iv) The slope of the plastic region of the true stress-strain curve20252m
Module 3: Mechanical Property Measurement
View this question on its own page →Choose the correct option:
In a standard tensile test on a ductile metal, Young's modulus is obtained from:
(i) The entire stress-strain curve up to fracture
(ii) The slope of the initial linear portion of the engineering stress-strain curve
(iii) The maximum load divided by original area
(iv) The slope of the plastic region of the true stress-strain curveQ1g. Choose the correct option: Which statement about hardness testing is most appropriate for steels? (i) Rockwell hardness directly gives Young's modulus (ii) Brinell hardness can be empirically related to ultimate tensile strength (iii) Vickers hardness is expressed in HRC units (iv) Hardness tests are unrelated to strength20252m
Module 3: Mechanical Property Measurement
View this question on its own page →Choose the correct option:
Which statement about hardness testing is most appropriate for steels?
(i) Rockwell hardness directly gives Young's modulus
(ii) Brinell hardness can be empirically related to ultimate tensile strength
(iii) Vickers hardness is expressed in HRC units
(iv) Hardness tests are unrelated to strengthQ1h. Choose the correct option: The main purpose of normalising a hypoeutectoid steel is to: (i) Produce very soft coarse pearlite for maximum ductility only (ii) Refine grain size and produce uniform fine pearlite for improved strength and toughness (iii) Form martensite for maximum hardness (iv) Produce spheroidised cementite for easy machining20252m
Module 4: Heat Treatment of Steel
View this question on its own page →Choose the correct option:
The main purpose of normalising a hypoeutectoid steel is to:
(i) Produce very soft coarse pearlite for maximum ductility only
(ii) Refine grain size and produce uniform fine pearlite for improved strength and toughness
(iii) Form martensite for maximum hardness
(iv) Produce spheroidised cementite for easy machiningQ1i. Choose the correct option: Identify the correct statement regarding case hardening/surface hardening processes: (i) Harden only high-carbon steels by through hardening (ii) Modify the surface composition by diffusion of carbon and/or nitrogen while keeping a tougher core (iii) Rely only in rapid quenching with no change in composition (iv) Use only flame or induction as heat sources20252m
Module 4: Heat Treatment of Steel
View this question on its own page →Choose the correct option:
Identify the correct statement regarding case hardening/surface hardening processes:
(i) Harden only high-carbon steels by through hardening
(ii) Modify the surface composition by diffusion of carbon and/or nitrogen while keeping a tougher core
(iii) Rely only in rapid quenching with no change in composition
(iv) Use only flame or induction as heat sourcesQ1j. Choose the correct option: Grey and spheroidal cast irons mainly differ in that the graphite phase is present as: (i) Flakes in grey iron and spheroidal nodules in spheroidal iron (ii) Cementite in grey iron and flakes in spheroidal iron (iii) Spheroidal nodules in grey iron and flakes in spheroidal iron (iv) Cementite in both alloys20252m
Module 5: Alloying of Steel
View this question on its own page →Choose the correct option:
Grey and spheroidal cast irons mainly differ in that the graphite phase is present as:
(i) Flakes in grey iron and spheroidal nodules in spheroidal iron
(ii) Cementite in grey iron and flakes in spheroidal iron
(iii) Spheroidal nodules in grey iron and flakes in spheroidal iron
(iv) Cementite in both alloysQ2a. Describe the three main types of metallic crystal structures (BCC, FCC, HCP) with their coordination numbers and packing factors.20257m
Module 1: Crystal Structure
View this question on its own page →Describe the three main types of metallic crystal structures (BCC, FCC, HCP) with their coordination numbers and packing factors.
Q2b. Classify imperfections in solids with one example each.20257m
Module 1: Crystal Structure
View this question on its own page →Classify imperfections in solids with one example each.
Q3a. Explain what is meant by a solid solution and distinguish between substitutional and interstitial solid solutions.20257m
Module 2: Alloys and Phase Diagrams
View this question on its own page →Explain what is meant by a solid solution and distinguish between substitutional and interstitial solid solutions.
Q3b. With the help of a labelled binary phase diagram, explain how to interpret: Phase fields, liquidus and solidus lines.20257m
Module 2: Alloys and Phase Diagrams
View this question on its own page →With the help of a labelled binary phase diagram, explain how to interpret: Phase fields, liquidus and solidus lines.
Q4a. Sketch the Fe-Fe_3C phase diagram and explain its key features.20257m
Module 2: Alloys and Phase Diagrams
View this question on its own page →Sketch the Fe-FeC phase diagram and explain its key features.
Q4b. Describe eutectic, peritectic, peritectoid and monotectic reactions, clearly stating the phase changes in each case.20257m
Module 2: Alloys and Phase Diagrams
View this question on its own page →Describe eutectic, peritectic, peritectoid and monotectic reactions, clearly stating the phase changes in each case.
Q5a. Explain how Young's modulus is obtained from the stress-strain curve and discuss the physical meaning of the linear elastic region.20257m
Module 3: Mechanical Property Measurement
View this question on its own page →Explain how Young's modulus is obtained from the stress-strain curve and discuss the physical meaning of the linear elastic region.
Q5b. Explain the concept and objectives of non-destructive testing (NDT) and contrast it with destructive mechanical testing.20257m
Module 3: Mechanical Property Measurement
View this question on its own page →Explain the concept and objectives of non-destructive testing (NDT) and contrast it with destructive mechanical testing.
Q6a. Define annealing, normalising, tempering and spheroidising of steel, stating the typical heating temperature range relative to critical temperatures, holding, and cooling conditions.20257m
Module 4: Heat Treatment of Steel
View this question on its own page →Define annealing, normalising, tempering and spheroidising of steel, stating the typical heating temperature range relative to critical temperatures, holding, and cooling conditions.
Q6b. Sketch and label a typical isothermal transformation (TTT) diagram for eutectoid steel.20257m
Module 4: Heat Treatment of Steel
View this question on its own page →Sketch and label a typical isothermal transformation (TTT) diagram for eutectoid steel.
Q7a. Explain the difference between a Time-Temperature-Transformation (TTT) diagram and a Continuous Cooling Transformation (CCT) diagram for steels.20257m
Module 4: Heat Treatment of Steel
View this question on its own page →Explain the difference between a Time-Temperature-Transformation (TTT) diagram and a Continuous Cooling Transformation (CCT) diagram for steels.
Q7b. Describe how to use TTT and CCT diagrams to predict the final microstructure and hardness for different cooling paths.20257m
Module 4: Heat Treatment of Steel
View this question on its own page →Describe how to use TTT and CCT diagrams to predict the final microstructure and hardness for different cooling paths.
Q8a. Explain the purpose of alloying in steels, naming at least four common alloying elements and summarising their main effects on mechanical properties.20257m
Module 5: Alloying of Steel
View this question on its own page →Explain the purpose of alloying in steels, naming at least four common alloying elements and summarising their main effects on mechanical properties.
Q8b. Classify stainless steels with their compositions and applications.20257m
Module 5: Alloying of Steel
View this question on its own page →Classify stainless steels with their compositions and applications.
Q9a. Write a short note on: Super alloy20257m
Q9b. Write a short note on: Surface hardening20257m
Module 4: Heat Treatment of Steel
View this question on its own page →Write a short note on: Surface hardening
Q9c. Write a short note on: Solid Solutions20257m
Module 2: Alloys and Phase Diagrams
View this question on its own page →Write a short note on: Solid Solutions
Q9d. Write a short note on: Binary Phase Diagrams20257m
Module 2: Alloys and Phase Diagrams
View this question on its own page →Write a short note on: Binary Phase Diagrams