Ball bearings are, usually, made from
Low carbon steel
High carbon steel
Medium carbon steel
Chrome steel
Correct Answer :
D. Chrome steel
Related Questions
Which of the following element results in presence of free graphite in C.I.?
Carbon
Sulphur
Silicon
Manganese
Neutral solution is one which has pH value
Greater than 7
Less than 7
Equal to 7
pH value has nothing to do with neutral solution
Machining properties of steel are improved by adding
Sulphur, lead, phosphorous
Silicon, aluminium, titanium
Vanadium, aluminium
Chromium, nickel
In grey cast iron, carbon is present in the form of
Cementite
Free carbon
Flakes
Spheroids
The carbon in the pig iron varies from
0.1 to 0.5 %
0.5 to 1 %
1 to 5 %
5 to 10 %
Which of the following statements are true for annealing of steels?
Steels are heated to 500 to 700°C
Cooling is done slowly and steadily
Internal stresses are relieved
All of these
The property of a material due to which it breaks with little permanent distortion, is called
Brittleness
Ductility
Malleability
Plasticity
Wrought iron
Is a ductile material
Can be easily forged or welded
Cannot stand sudden and excessive shocks
All of these
Gamma iron exits at following temperature
Room temperature
Near melting point
Between 1400°C and 1539°C
Between 910°C and 1400°C
The presence of hydrogen in steel causes
Reduced neutron absorption cross-section
Improved Weldability
Embrittlement
Corrosion resistance
Brass (alloy of copper and zinc) is an example of
Substitutional solid solution
Interstitial solid solution
Intermetallic compounds
All of the above
The machinability of aluminium increases when __________ is added to aluminium.
Copper
Magnesium
Silicon
Lead and bismuth
Ball bearings are, usually, made from
Low carbon steel
High carbon steel
Medium carbon steel
Chrome steel
The strength is the ability of a material to resist
Deformation under stress
Externally applied forces with breakdown or yielding
Fracture due to high impact loads
None of these
Which of the following is an amorphous material?
Mica
Silver
Lead
Glass
There are fourteen atoms in a unit cell of
Body centred cubic space lattice
Face centred cubic space lattice
Close packed hexagonal space lattice
None of these
Which of the following impurity in cast iron promotes graphite nodule formation and increases the fluidity of the molten metal?
Silicon
Sulphur
Manganese
Phosphorus
The ability of a material to resist fracture due to high impact loads, is called
Strength
Stiffness
Toughness
Brittleness
The alloying element which increases residual magnetism and coercive magnetic force in steel for magnets is
Chromium
Nickel
Vanadium
Cobalt
Macrostructure of a material is, generally, examined by
Naked eye
Optical microscope
Metallurgical microscope
X-ray techniques
Pick up the wrong statement Nickel and chromium in steel help in
Providing corrosion resistance
Improving machining properties
Providing high strength at elevated temperatures
Raising the elastic limit
Induction hardening is the process of
Hardening surface of work-piece to obtain hard and wear resistant surface
Heating and cooling rapidly
Increasing hardness throughout
Inducing hardness by continuous process
The percentage of carbon in cast iron varies from
0.1 to 0.5
0.5 to 1
1 to 1.7
1.7 to 4.5
The hardness of steel increases if it contains
Austenite
Martensite
Pearlite
Cementite
When a steel containing ________ 0.8% carbon is cooled slowly below the lower critical point, it consists of ferrite and pearlite.
Equal to
Less than
More than
None of these
In low carbon steels, presence of small quantities of sulphur improves
Weldability
Formability
Machinability
Hardenability
White cast iron has
Carbon in the form of carbide
Low tensile strength
High compressive strength
All of these
The crystal of alpha iron is
Body centered cubic
Face centered cubic
Hexagonal close packed
Cubic structure
The unique property of cast iron is its high
Malleability
Ductility
Surface finish
Damping characteristics
Blast furnace is used to produce
Pig iron
Cast iron
Wrought iron
Steel