Engineering Materials Practice Set-5

Page 1 of 4

1. Tin base white metals are used where the bearings are subjected to

Elevated temperatures

High pressure and load

Large surface wear

Light load and pressure

2. Iron-carbon alloys containing 1.7 to 4.3% carbon are known as

Hypereutectic cast irons

Eutectic cast irons

None of these

Hypoeutectic cast irons

3. When elements like nickel, chromium, copper and molybdenum are added to the molten cast iron, it produces

White cast iron

Alloy cast iron

Nodular cast iron

Malleable cast iron

4. In full annealing, the hypo eutectoid steel is heated from 30°C to 50°C above the upper critical temperature and then cooled

Any one of these

In still air

Suddenly in a suitable cooling medium

Slowly in the furnace

5. Foundry crucible is made of

German silver

Lead

Graphite

Mild steel

6. The brown smoke during the operation of a Bessemer converter indicates that the

Silicon and manganese has burnt and carbon has started oxidizing

The converter must be titled to remove the contents of the converter

The brown smoke does not occur during the operation of a Bessemer converter

Air is burning out silicon and manganese

7. Following elements have face-centered cubic structure

Gamma iron (910° to 1400°C), Cu, Ag, Au, Al, Ni, Pb, Pt

Mg, Zn, Ti, Zr, Br, Cd

All of the above

A iron (below 910°C and between 1400 to 1539°C), W

8. When low carbon steel is heated up to lower critical temperature

The average grain size is a minimum

The grain size first increases and then decreases very rapidly

There is no change in grain size

The grain size increases very rapidly

9. Slow plastic deformation of metals under a constant stress is known as

Endurance

Creep

Plastic deformation

Fatigue

10. Materials after cold working are subjected to following process to relieve stresses

Hot working

Normalizing

Annealing

Tempering

Page 2 of 4

11. The coordination number of a face centered cubic space lattice is

Twenty

Twelve

Eighteen

Six

12. Malleability of a material can be defined as

Ability to undergo large permanent deformations in tension

All of the above

Ability to recover its original form

Ability to undergo large permanent deformations in compression

13. The charge is fed into the blast furnace through the

Bosh

Throat

Tyres

Stack

14. Closed packed hexagonal space lattice is found in

Alpha-iron, tungsten, chromium and molybdenum

None of the above

Gamma-iron, aluminium, copper, lead, silver and nickel

Zinc, magnesium, cobalt, cadmium, antimony and bismuth

15. The type of space lattice found in alpha-iron is

Close packed hexagonal space lattice

Face centered cubic space lattice

Body centered cubic space lattice

None of these

16. Which of the following metal is used in making electrical resistance wire for electric furnaces and heating elements?

Nichrome

Babbitt metal

Phosphor bronze

Monel metal

17. A small percentage of boron is added to steel in order to

Increase wear resistance

Increase endurance strength

Increase hardenability

Reduce machinability

18. Which of the following is not the correct method of increasing fatigue limit?

Shot peening

Cold working

Nitriding of surface

Surface decarburisation

19. The ultimate tensile strength of low carbon steel by working at a high strain rate will

Increase

Remain constant

Decrease

First increase and then decrease

20. Balls for ball bearings are made of

Cast iron

Mild steel

Carbon-chrome steel

Stainless steel

Page 3 of 4

21. Neutral solution is one which has pH value

Greater than 7

pH value has nothing to do with neutral solution

Less than 7

Equal to 7

22. Mild steel belongs to the following category

High carbon steel

Low carbon steel

Alloy steel

Medium carbon steel

23. Which is false statement about case hardening? Case hardening is done by

Induction hardening

Cyaniding

Nitriding

Electroplating

24. The ability of a material to resist softening at high temperature is known as

Hot hardness

Hot tempering

Creep

Fatigue

25. White cast iron has

Low tensile strength

All of these

High compressive strength

Carbon in the form of carbide

26. The percentage of carbon in low carbon steel is

0.05%

0.5%

0.3%

0.15%

27. The molecules in a solid move

In a random manner

Back and forth like tiny pendulums

In a haphazard way

In circular motion

28. Which of the following display properties similar to that of steel?

(C) Both (A) and (B)

(D) None of these

(A) Blackheart cast iron

(B) Whiteheart cast iron

29. The steel widely used for motor car crankshafts is

Silicon steel

Nickel steel

Chrome steel

Nickel-chrome steel

30. Which is false statement about properties of aluminium?

Modulus of elasticity is fairly low

Creep strength limits its use to fairly low temperatures

Wear resistance is very good

Fatigue strength is not high

Page 4 of 4

31. A material is known as allotropic or polymorphic if it

Has a fixed structure under all conditions

Has its atoms distributed in a random pattern

Exists in several crystal forms at different temperatures

Responds to heat treatment

32. Recrystallization temperature is one

At which crystals grow bigger in size

At which new spherical crystals first begin to form from the old deformed one when a strained metal is heated

At which change of allotropic form takes place

At which crystals first start forming from molten metal when it is cooled

33. The stiffness is the ability of a material to resist

None of the above

Externally applied forces with breakdown or yielding

Deformation under stress

Fracture due to high impact loads

34. Delta iron occurs at temperature of

Above melting point

Between 910°C and 1400°C

Between 1400°C and 1539°C

Room temperature

35. Which of the following constituents of steels is softest and least strong?

Cementite

Austenite

Ferrite

Pearlite

36. Brass is an alloy of

Copper and zinc

Copper and tin

Copper, tin and zinc

None of these

37. Isotropic materials are those which have the same

Electric and magnetic properties in all directions

Thermal properties in all directions

Elastic properties in all directions

Stresses induced in all directions

38. The property of a material essential for spring materials is

Ductility

Stiffness

Resilience

Plasticity

39. The elastic stress strain behavior of rubber is

Nonlinear

No fixed relationship

Plastic

Linear

40. Lead is poured into the joint between two pipes. These pipes may be made of

Cast iron

Concrete

Vitrified clay

Asbestos cement

Engineering Materials Practice Set-5

Related

Leave a ReplyCancel reply

Secured Payments

Protection

Engineering Materials Practice Set-5

Share this Now with Friends:

Related

Leave a ReplyCancel reply

Secured Payments

Protection