AP PGECET 2024 Metallurgy Question Paper with Answer Key PDF

Question 1:

Which of the following does not have FCC crystal structure?

• (1) Copper
• (2) Sodium
• (3) Lead
• (4) Aluminium

Froth flotation is most suitable for treating

• (1) Iron ores
• (2) Quartzite
• (3) Sulphide ores
• (4) Carbonates

Which of the following is a line defect found in metal crystal?

• (1) Vacancies
• (2) Grain boundaries
• (3) Stacking faults
• (4) Dislocations

Softest phase in Fe-Fe\(_3\)C phase diagram is

• (1) Austenite
• (2) Cementite
• (3) \(\alpha\) ferrite
• (4) Martensite

At room temperature, Iron is ........ in lattice arrangement

• (1) HCP
• (2) BCC
• (3) Tetragonal
• (4) FCC

The term Ledeburite in steels refers to

• (1) An intermetallic compound
• (2) A solid solution
• (3) An inclusion
• (4) A mixture of two phases

The eutectoid reaction in steel occurs at

• (1) 723°C
• (2) 1146°C
• (3) 1495°C
• (4) 910°C

Peritectic reaction among the following is

• (1) \(\alpha\) + L \(\xrightarrow{Cooling}\) \( \beta \)
• (2) L \(\xrightarrow{Cooling}\) \(\beta\)
• (3) \(\alpha\) \(\xrightarrow{Cooling}\) \(\beta\)
• (4) L \(\xrightarrow{Cooling}\) \(\beta\) + S

Carbon content in hypo eutectic cast iron is

• (1) 0.08-0.8%
• (2) 4.3-6.67%
• (3) 2.0-4.3%
• (4) 0.8-2.0%

Etching solution used for Copper is

• (1) Nital
• (2) 50% NH\(_4\)OH
• (3) Picral
• (4) 1% HF in water

Toughness of a material implies

• (1) Impact strength
• (2) Creep resistance
• (3) Stress relieving
• (4) Machinability

Martensite transformation occurs by

• (1) Nucleation-and-growth phenomenon
• (2) Diffusionless transformation
• (3) Lattice diffusion
• (4) Spinodal decomposition

The fine austenite grain size in steel increases

• (1) Corrosion resistance
• (2) Hardenability
• (3) Creep strength
• (4) Impact toughness

Which mode of size reduction is used by Jaw crushers?

• (1) Impact
• (2) Compression
• (3) Cutting
• (4) Attrition

Which of the following is a metal refining process?

• (1) Roasting
• (2) Smelting
• (3) Vacuum arc remelting
• (4) Calcination

Kick's law relates to

• (1) Final particle size
• (2) Feed size
• (3) Ore size
• (4) Energy consumption

Pine oil used in froth flotation technique acts as a

• (1) Frother
• (2) Collector
• (3) Crusher
• (4) Modifier

Leaching of ore is done in ...... method of metal extraction process

• (1) Smelting
• (2) Pyro metallurgical
• (3) Hydro metallurgical
• (4) Electro metallurgical

Which of the following is not a function of coke in the blast furnace?

• (1) Produce heat
• (2) Generate reducing gases
• (3) Act as spacer
• (4) Act as a flux

The size of blast furnace coke is about

• (1) 10-30 mm
• (2) 25-80 mm
• (3) 80-100 mm
• (4) 25-40 mm

Which is an acidic refractory?

• (1) Magnesite
• (2) Dolomite
• (3) Fireclay
• (4) Chrome magnesite

Which is the hardest structure that appears on the Fe-C equilibrium diagram?

• (1) Ferrite
• (2) Pearlite
• (3) Austenite
• (4) Cementite

Which of the following statement is wrong in Hume Rothery rules?

• (1) Solute and solvent atoms possess almost equal diameters
• (2) The crystal structure of two metals is the same
• (3) The chemical affinity of the two metals is high
• (4) Lower chemical valence metals will dissolve more in higher valence than vice versa

Segar cones are used for the determination of

• (1) Electrical conductivity
• (2) Softening temperature of refractories
• (3) Spalling resistance
• (4) Resistance to slag attack

Sillimanite is a

• (1) Basic refractory
• (2) Insulating refractory
• (3) Neutral refractory
• (4) High alumina refractory

The structure produced by martempering of steel is

• (1) Pearlite
• (2) Austenite
• (3) Martensite
• (4) Bainite

Which of the following treatments is used for imparting ductility in the metals?

• (1) Annealing
• (2) Normalizing
• (3) Hardening
• (4) Tempering

Sub-zero treatment is used for

• (1) Bainite transformation
• (2) Pearlite transformation
• (3) Austenite transformation
• (4) Retained Austenite transformation

Hardenability of a steel is measured in terms of

• (1) Its iron content
• (2) Its carbon content
• (3) The depth martensite from the surface
• (4) The depth of Austenite from the surface

Compound formed during precipitation hardening of Al-Cu alloys is

• (1) CuAl
• (2) CuAl₂
• (3) Cu₂Al₃
• (4) Cu₃Al₂

The structure produced by Austempering of steel is

• (1) Austenite
• (2) Pearlite
• (3) Bainite
• (4) Martensite

Sorbite is a mixture

• (1) Ferrite and cementite
• (2) Austenite and Ferrite
• (3) Ferrite and pearlite
• (4) Ferrite and martensite

Major alloying addition in spring steels is

• (1) Aluminium
• (2) Silicon
• (3) Titanium
• (4) Nickel

Which of the following is not a mixture of ferrite and cementite?

• (1) Troostite
• (2) Pearlite
• (3) Ledeburite
• (4) Martensite

Malleable cast iron is obtained by controlled heat treatment of

• (1) Grey cast iron
• (2) Nodular cast iron
• (3) White cast iron
• (4) Flake graphite cast iron

The diffusion inequality of components in a binary solution of alloys is given by

• (1) Cottrell effect
• (2) Graham’s law
• (3) Fick’s law
• (4) Kirkendall effect

Stress causing a deformation of ........ % is called yield strength

• (1) 1.0
• (2) 0.01
• (3) 0.2
• (4) 3.3

The diameter of the ball in BHN test for steel and other hard materials is

• (1) 5 mm
• (2) 10 mm
• (3) 25 mm
• (4) 50 mm

In which of the following hardness tests is the Brale indenter used for indentation?

• (1) Vickers test
• (2) Shore test
• (3) Brinell test
• (4) Rockwell test

The ability of a material to withstand suddenly applied loads is called

• (1) Creep strength
• (2) Hardness
• (3) Impact strength
• (4) Fatigue strength

The fatigue limit of metals is decreased by

• (1) Carburizing
• (2) Nitriding
• (3) Carbonitriding
• (4) Decarburizing

Plastic deformation of metal below its recrystallization temperature is called

• (1) Cold working
• (2) Hot working
• (3) Deep drawing
• (4) Tempering

At what temperature grains and grain boundaries will have equal strength?

• (1) Recrystallization temperature
• (2) Curie temperature
• (3) Absolute zero temperature
• (4) Equi cohesive temperature

Which method is not used to measure the residual stress of a given material?

• (1) Magnetic particle method
• (2) Radiography
• (3) Dye-penetrant method
• (4) Ultrasonic testing

Which of the following is not used for the manufacture of bearing materials?

• (1) Steel
• (2) Copper
• (3) Babbit materials
• (4) Pig iron

Hooke’s law holds good up to

• (1) Plastic limit
• (2) Proportional limit
• (3) Yield point
• (4) Ultimate tensile strength

In CO₂ moulding process ...... is used as binder

• (1) Water
• (2) Dextrine
• (3) Sodium silicate
• (4) Bentonite

Which of the following is a powder production method?

• (1) Rolling
• (2) Tapping
• (3) Forging
• (4) Atomization

Copper materials exhibit ........ fracture

• (1) Flat
• (2) Combined
• (3) Cup and cone
• (4) Helical

Which of the following is an ore of Titanium?

• (1) Bauxite
• (2) Ilmenite
• (3) Chacopyrite
• (4) Limonite

Cementite (Fe\(_3\)C) crystal structure is

• (1) Orthorhombic
• (2) BCT
• (3) HCP
• (4) FCC

Most closely packed planes in face-centered cubic lattice are

• (1) (110)
• (2) (112)
• (3) (100)
• (4) (111)

Stacking faults are ....... imperfections

• (1) Point
• (2) Line
• (3) Surface
• (4) Volume

Which of the following alloys can be strengthened by Age-hardening?

• (1) Cu - Sn
• (2) Cu - Zn
• (3) Cu - Ni
• (4) Al - Cu

Surgical instruments are made of

• (1) Plain carbon steels
• (2) Titanium alloys
• (3) Stainless steels
• (4) Copper alloys

Razor blades are made with ....... % of carbon steel

• (1) Low carbon steel
• (2) Medium carbon steel
• (3) Mild steel
• (4) High carbon steel

Zirconium alloys are used in nuclear reactors as

• (1) Cladding material
• (2) Catalyst
• (3) Moderator
• (4) Fuel

To obtain high corrosion resistance of the steel, which of the following elements are added?

• (1) Carbon, Silicon
• (2) Chromium, Nickel
• (3) Carbon, Tungsten
• (4) Copper, Titanium

Dephosphorization is favorable in the following conditions of the steel-making process

• (1) Acid slag and oxidizing atmosphere
• (2) Acid slag and reducing atmosphere
• (3) Basic slag and oxidizing atmosphere
• (4) Basic slag and reducing atmosphere

Finest particles in blast furnace gas are removed by

• (1) Dust catcher
• (2) Electrostatic precipitator
• (3) Wet scrubber
• (4) Blast furnace stoves

Which of the following is not an iron ore?

• (1) Banded Hematite Quartzite (BHQ)
• (2) Hematite
• (3) Goethite
• (4) Chalcopyrite

Which of the following is a chief source of sulfur entry in the blast furnace?

• (1) Iron ore
• (2) Coke
• (3) Sinter
• (4) Flux

The favorable conditions for desulphurization of iron are

• (1) Both slag basicity and temperature should be high
• (2) Atmosphere should be oxidizing
• (3) Slag basicity should be low and temperature should be high
• (4) Slag should be viscous

Blue dust is

• (1) Generated during iron making
• (2) Generated during steel making
• (3) Generated during mining
• (4) Dust collected from exhaust gases

Iron ore sintering employs the principle of ........

• (1) Down draught sintering
• (2) Up draught sintering
• (3) Smelting
• (4) Roasting

High alumina content in the blast furnace slag .......

• (1) Increases its melting point, but decreases its viscosity
• (2) Does not affect its melting point but increases its viscosity
• (3) Decreases both its melting point but increases its viscosity
• (4) Increases both its melting point and viscosity

Lever rule is used to evaluate the .......

• (1) Relative amounts of two phases in equilibrium at any specified temperature
• (2) Chemical composition of the phases of an alloy in equilibrium at any specified temperature
• (3) Residual stresses in a given alloy
• (4) Number of phases present in a given alloy

Catch carbon technique is employed in LD steel making process to produce

• (1) Low carbon steel
• (2) High alloy steel
• (3) High carbon steel
• (4) Killed steel

Composites strength is evaluated by .......

• (1) Hooke's law
• (2) Power law
• (3) Fick's law
• (4) Rule of mixture

Salamander tapping in blast furnace is done after

• (1) Blowing out
• (2) Banking
• (3) Back draughting
• (4) Blowing in

Which of the following is a creep deformation mechanism?

• (1) Grain sliding
• (2) Grain boundary sliding
• (3) Dislocations pile up
• (4) Strain hardening

Which of the following is not a metal matrix composites fabrication technique?

• (1) Vortex method
• (2) Squeeze casting
• (3) Pultrusion
• (4) Duralcan process

Critical fibre length of a composite is expressed by the following equation

• (1) L\(_c\) = [\sigma × d] / [2\tau\(_C\)]
• (2) L\(_c\) = [\sigma + d] / [2\tau\(_C\)]
• (3) L\(_c\) = [2\tau\(_C\)] / [\sigma × d] /
• (4) L\(_c\) = [\sigma - d] / [2\tau\(_C\)]

Which of the following employs a bottom blowing operation?

• (1) L.D. converter
• (2) Rotor
• (3) OBM
• (4) Kaldo furnace

In Basic steel making process, ....... slag is prepared to remove the impurities

• (1) Dry slag
• (2) Wet slag
• (3) Neutral slag
• (4) Reducing slag

Killing of the steel bath is aimed to remove .......

• (1) Carbon
• (2) Sulphur
• (3) Phosphorous
• (4) Oxygen

Glass ceramics possess ......

• (1) Fine grain structure
• (2) Non-crystalline structure
• (3) Hard and brittle
• (4) Low impact strength

Which of the following is an oxide ore of copper?

• (1) Chalcocite
• (2) Chalcopyrite
• (3) Malachite
• (4) Bornite

In Parkes process, desilvering of molten lead is affected by the addition of

• (1) Carbon
• (2) Copper
• (3) Aluminum
• (4) Zinc

The use of bacterial leaching is

• (1) Refining of metals
• (2) Fast recovery of metal values
• (3) In situ-leaching of low-grade ores
• (4) Leaching of enriched ores

Lead-free solders are made with

• (1) Iron based alloys
• (2) Tin based alloys
• (3) Magnesium based alloys
• (4) Aluminium based alloys

Which is the most weldable of all metals?

• (1) Plain carbon steels
• (2) Stainless steels
• (3) Aluminium
• (4) Brass

The formation of corrosion retarding films on metal surfaces is known as

• (1) Polarization
• (2) Passivation
• (3) Cavitation
• (4) Pitting

Example of a sacrificial anode which is used in the protection of underground pipelines is

• (1) Steel
• (2) Platinum
• (3) Graphite
• (4) Magnesium

Enthalpy "H" is defined as

• (1) H = E - PV
• (2) H = E + PV
• (3) H = F - TS
• (4) H = F + PV

The main cause to exist congruent melting alloys in a given isomorphous system is

• (1) Large atomic size difference between solvent and solute
• (2) Variation in crystal structures of solvent and solute
• (3) Variation in chemical valance factor of solvent and solute
• (4) Variation in chemical composition of solvent and solute

Degrees of freedom at triple point will be

• (1) 0
• (2) 1
• (3) 2
• (4) 3

The free energy changes at equilibrium is

• (1) Positive
• (2) Negative
• (3) Intermediate
• (4) Zero

For a spontaneous process

• (1) Both Free energy and entropy decrease
• (2) Free energy increases
• (3) Free energy decreases whereas the entropy increases
• (4) Free energy is zero

Entropy is a measure of

• (1) Disorder of a system
• (2) Orderly behavior of a system
• (3) Only temperature changes of the system
• (4) Equilibrium of system

Ellingham diagrams for M ~MOx reactions is a plot of

• (1) \(\Delta G\) vs T
• (2) \(\Delta G^{\circ}\) vs T
• (3) \(\Delta G^{\circ}\) vs 1/T
• (4) \(\Delta G^{\circ}\) vs 1/T

In Ellingham diagrams, the reaction that is parallel to the temperature axis is

• (1) \(2CO + O_2 = 2CO_2\)
• (2) \(2C + O_2 = 2CO_2\)
• (3) \(C + O_2 = CO_2\)
• (4) \(2Zn + O_2 = 2ZnO\)

Dental alloys are casted by ...... process

• (1) True centrifugal
• (2) Shell moulding
• (3) CO2 moulding process
• (4) Investment casting

The ideal theoretical shape of a Riser is

• (1) Conical
• (2) Rectangular
• (3) Cylindrical
• (4) Cubic

Plastic goods are usually produced by

• (1) Shell moulding
• (2) Injection moulding
• (3) Wet sand moulding
• (4) Dry sand moulding

Blow holes are casting defects caused by

• (1) Excessive gaseous substances not able to escape
• (2) Discontinuity in metal casting resulting from hindered contraction
• (3) Two streams of metals that are too cold to figure properly
• (4) Some sand shearing from the cope surface

Which of the following is a eutectic reaction?

• (1) \( L \to Cooling \alpha \)
• (2) \( L \to Cooling \alpha + \beta \)
• (3) \( L \to Cooling \beta \)
• (4) \( \alpha + L \to Cooling \beta \)

Which is the top-down approach method for the synthesis of Nano materials?

• (1) Chemical vapour deposition
• (2) Sol-Gel technique
• (3) High energy ball milling
• (4) Chemical precipitation method

TIG is especially useful in welding for the following alloys

• (1) Stainless steels
• (2) Aluminium and its alloys
• (3) Titanium and its alloys
• (4) Cast Irons

Electrode is consumed in ........ welding process

• (1) Gas
• (2) TIG
• (3) Thermit
• (4) Arc

Cold working of metal reduces its

• (1) Ductility
• (2) Hardness
• (3) Ultimate tensile strength
• (4) Electrical resistance

The collapsible toothpaste tube is produced by ....... extrusion

• (1) Direct
• (2) Impact
• (3) Tube
• (4) Indirect

Dislocation tangles are the regions of

• (1) Defect free areas
• (2) Dislocation free areas
• (3) Low dislocation density areas
• (4) High dislocation density areas

Critical resolved shear stress is expressed by the following equation

• (1) \(\tau_R = \frac{P}{A} \cos \phi \sin \lambda\)
• (2) \(\tau_R = \frac{P}{A} \sin \phi \cos \lambda\)
• (3) \(\tau_R = \frac{P}{A} \cos \phi \cos \lambda\)
• (4) \(\tau_R = \frac{P}{A} \sin \phi \sin \lambda\)

Anti-Phase Boundaries (APB) are existing in ...... strengthening mechanism

• (1) Grain boundary strengthening mechanism
• (2) Solid solution strengthening mechanism
• (3) Precipitation hardening strengthening mechanism
• (4) Strain hardening strengthening mechanism

Which alloying element does not shift TTT diagram or does not retard the transformation of austenite to pearlite or bainite?

• (1) Cobalt
• (2) Nickel
• (3) Copper
• (4) Aluminium

When two different metals placed in contact, when one is heated, an EMF is generated. This effect is called as

• (1) Thomson effect
• (2) Temperature effect
• (3) Seebeck effect
• (4) Junction-diode effect

Calculate the Pilling-Bedworth ratio when Fe oxides to FeO. The atomic weight of Fe is 55.8 gm, the atomic weight of Oxygen is 16 gm, density of Fe is 7.87 gm/cc and density of FeO is 5.70 gm/cc

• (1) 0.777
• (2) 3.777
• (3) 2.777
• (4) 1.777

Solution of the system of equations \( 3x + y + 2z = 3 \), \( 2x - 3y - z = -3 \), \( x + 2y + z = 4 \)

• (1) \( (1, 2, 1)
• (2) \( (1, 2, -1)
• (3) \( (2, 3, 1)
• (4) \( (4, 3, 2)

If \( f(x) = (x^2 - 16)^2 \), where \( x \) is real, \( f(x) \) has

• (1) Two maxima and one minimum
• (2) One maxima and 2 minima
• (3) Three minima
• (4) Three maxima

If \( A \) is an orthogonal matrix, then \( A^{-1} \) is

• (1) Symmetric
• (2) Skew-symmetric
• (3) Orthogonal
• (4) Hermitian

If \( \mathbf{f} = f_1(y, z) \hat{i} + f_2(z, x) \hat{j} + f_3(x, y) \hat{k} \), then \( \mathbf{f} \) is

• (1) Irrotational
• (2) Solenoidal
• (3) Both Irrotational \& Solenoidal
• (4) Gradient

The work done in displacing a particle from \( r = 0 \) to \( r = 1 \) in a curve \( x = t^2 + 1 \) and \( z = t^2 + 1 \) in a force field \( \mathbf{F} = (2xy, 3x, -5z) \) is

• (1) \(-\frac{19}{2} \)
• (2) \(-\frac{14}{3} \)
• (3) \(-\frac{21}{2} \)
• (4) \( 5 \)

If \( \mathbf{a} \) is a constant vector, then \( div[\mathbf{a} \times (\mathbf{r} \times \mathbf{a})] \) is

• (1) \( 2a^2 \)
• (2) \( 3a^2 \)
• (3) \( 6a^2 \)
• (4) \( 4a^2 \)

If \( \mathbf{F} = ax \hat{i} + by \hat{j} + cz \hat{k} \), where \( a, b, c \) are constants, then

• (1) 0
• (2) \( \frac{4}{3} \pi (a + b + c)^2 \)
• (3) \( \frac{4}{3} \pi (a + b + c) \)
• (4) 1

Solution of the differential equation \( xy \frac{dy}{dx} = 1 + x + y + xy \) is

• (1) \( \log(x(1+y)) = c \)
• (2) \( (y - x) \log(x(1 + y)) = c \)
• (3) \( (y + x) \log(x) = c \)
• (4) \( \log(x(1 + y)) = c \)

What is the correct formula for Runge-Kutta 3rd order method?

• (1) \( y = y_0 + \frac{1}{6}(k_1 + 2k_2 + 3k_3) \)
• (2) \( y = y_0 + \frac{1}{3}(k_1 + 4k_2 + k_3) \)
• (3) \( y = y_0 + \frac{1}{6}(k_1 + 4k_2 + k_3) \)
• (4) \( y = y_0 + \frac{1}{6}(k_1 + k_2) \)

One of the two events must occur. The chance of one is \( \frac{2}{3} \) of the other, then odds in favor of the other are

• (1) \( 3:2 \)
• (2) \( 1:3 \)
• (3) \( 3:1 \)
• (4) \( 2:3 \)

The coefficient of correlation is independent of

• (1) Change of scale only
• (2) Change of origin only
• (3) Both change of scale \& origin
• (4) No change

If \( x^2 - x - 4 = 0 \) by bisection method, first two approximations \( x_1 \) and \( x_2 \) are 1 and 2, then \( x_3 \) is

• (1) 1.2
• (2) 1.3
• (3) 1.4
• (4) 1.5