The surface hardness of the following order is achieved by nitriding operation
600 VPN
1500 VPN
1000 to 1100 VPN
250 VPN
Correct Answer :
C. 1000 to 1100 VPN
Related Questions
The type of space lattice found in alpha-iron is
Face centred cubic space lattice
Body centred cubic space lattice
Close packed hexagonal space lattice
None of these
Pure iron is the structure of
Ferrite
Pearlite
Austenite
Ferrite and cementite
The metal suitable for bearings subjected to light loads, is
Silicon bronze
White metal
Monel metal
Phosphor bronze
In basic Bessemer process, the furnace is lined with
Silica bricks
A mixture of tar and burnt dolomite bricks
Both (A) and (B)
None of these
When low carbon steel is heated up to lower critical temperature
There is no change in grain size
The average grain size is a minimum
The grain size increases very rapidly
The grain size first increases and then decreases very rapidly
Nodular cast iron is produced by adding ________ to the molten cast iron.
Nickel
Chromium
Copper
Magnesium
Beryllium bronze contains
60% copper and 40% beryllium
80% copper and 20% beryllium
97.75% copper and 2.25% beryllium
99% copper and 1% beryllium
Cast iron is a
Ductile material
Malleable material
Brittle material
Tough material
Iron is
Paramagnetic
Ferromagnetic
Ferroelectric
Dielectric
The ultimate tensile strength of low carbon steel by working at a high strain rate will
Decrease
Increase
Remain constant
First increase and then decrease
Maximum percentage of carbon in austenite is
0.025 %
0.26 %
0.8 %
1.7 %
Malleable cast iron is produced
By adding magnesium to molten cast iron
By quick cooling of molten cast iron
From white cast iron by annealing process
None of these
A small percentage of boron is added to steel in order to
Increase hardenability
Reduce machinability
Increase wear resistance
Increase endurance strength
Cementite consist of
13% carbon and 87% ferrite
13% cementite and 87% ferrite
13% ferrite and 87% cementite
6.67% carbon and 93.33% iron
Cartridge brass can be
Cold rolled into sheets
Drawn into wires
Formed into tube
Any one of these
The metallic structure of mild steel is
Body centred cubic
Face centred cubic
Hexagonal close packed
Cubic structure
Large forgings, crank shafts, axles normally contain carbon up to
0.05 to 0.20 %
0.20 to 0.45 %
0.45 to 0.55 %
0.55 to 1.0 %
Nimonic contains __________ percentage of nickel as that of Inconel.
Same
Less
More
None of these
The ratio of the volume occupied by the atoms to the total volume of the unit cell is called
Coordination number
Atomic packing factor
Space lattice
None of these
Addition of silicon to aluminium results in
Improvement of casting characteristics
Improvement of corrosion resistance
One of the best known age and precipitation hardening systems
Improving machinability
German silver contains
1% silver
2.5% silver
5% silver
10% silver
High carbon steel carries carbon percentage
0.1 to 0.3 %
0.3 to 0.6 %
0.6 to 0.8 %
0.8 to 1.5 %
The steel widely used for motor car crankshafts is
Nickel steel
Chrome steel
Nickel-chrome steel
Silicon steel
The surface hardness of the following order is achieved by nitriding operation
600 VPN
1500 VPN
1000 to 1100 VPN
250 VPN
In induction hardening ________ is high.
Current
Voltage
Frequency
Temperature
Which of the following iron exist between 910°C and 1403°C?
α-iron
β-iron
γ-iron
δ-iron
The toughness of a material __________ when it is heated.
Remain same
Decreases
Increases
None of these
The stiffness is the ability of a material to resist
Deformation under stress
Fracture due to high impact loads
Externally applied forces with breakdown or yielding
None of the above
In mottled cast iron, carbon is available in
Free form
Combined form
Nodular form
Partly in free and partly in combined state
Which of the following element results in presence of free graphite in C.I.?
Carbon
Sulphur
Silicon
Manganese