Hardness of steel depends on
Amount of carbon it contains
The shape and distribution of the carbides in iron
Method of fabrication
Contents of alloying elements
Correct Answer :
B. The shape and distribution of the carbides in iron
Related Questions
Materials after cold working are subjected to following process to relieve stresses
Hot working
Tempering
Normalising
Annealing
Blast furnace is used to produce
Pig iron
Cast iron
Wrought iron
Steel
An important property of high silicon (12-18%) cast iron is the high
Hardness
Brittleness
Plasticity
Ductility
Cast iron is characterised by minimum of following percentage of carbon
0.2 %
0.8 %
1.3 %
2 %
Nickel when added to copper improves
Machinability
Hardness
Hardness and strength
Strength and ductility
The material in which the atoms are arranged regularly in some directions but not in others, is called
Amorphous material
Mesomorphous material
Crystalline material
None of these
Monel metal is an alloy of
Nickel and copper
Nickel and chromium
Nickel, Chromium and iron
Copper and chromium
Cupola produces following material
Cast iron
Pig iron
Wrought iron
Malleable iron
Hardness of lower bainite (tempered martensite) is about
RC 65
RC 48
RC 57
RC 80
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
Pearlite consists of
13% carbon and 87% ferrite
13% cementite and 87% ferrite
13% ferrite and 87% cementite
6.67% carbon and 93.33% iron
German silver is an alloy of
Silver and some impurities
Refined silver
Nickel, Copper and zinc
Nickel and copper
Normalising of steel is done to
Refine the grain structure
Remove strains caused by cold working
Remove dislocations caused in the internal structure due to hot working
All of the above
Which of the following elements does not impart hardness to steel?
Copper
Chromium
Nickel
Silicon
Monel metal contains
63 to 67% nickel and 30% copper
88% copper and 10% tin and rest zinc
Alloy of tin, lead and cadmium
Malleable iron and zinc
The ultimate tensile strength and yield strength of most of the metals, when temperature falls from 0 to 100°C will
Increase
Decrease
Remain same
First increase and then decrease
In spheroidising process, the steel is
Heated below the lower critical temperature and then cooled slowly
Heated up to the lower critical temperature and then cooled in still air
Heated slightly above the lower critical temperature and then cooled slowly to a temperature of 600°C
None of the above
When low carbon steel is heated up to upper 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
Combined carbon in iron makes the metal
Soft and gives coarse grained crystalline structure
Soft and gives a fine grained crystalline structure
Hard and gives a coarse grained crystalline structure
Hard and gives a fine grained crystalline structure
Carbon steel is
Made by adding carbon in steel
Refined from cast iron
An alloy of iron and carbon with varying quantities of phosphorus and sulphur
Extensively used for making cutting tools
The electric process of steel making is especially adapted to
Alloy and carbon tool steel
Magnet steel
High speed tool steel
All of these
Iron ore is, usually, found in the form of
Oxides
Carbonates
Sulphides
All of these
For the allotropic forms of iron, the points of arrest are
The points where no further change occurs
Constant for all metals
The points where there is no further flow of metal
The points of discontinuity
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
Mild steel belongs to the following category
Low carbon steel
Medium carbon steel
High carbon steel
Alloy steel
The defect which takes place due to imperfect packing of atoms during crystallisation is known as
Line defect
Surface defect
Point defect
None of these
Lead is poured into the joint between two pipes. These pipes may be made of
Cast iron
Vitrified clay
Asbestos cement
Concrete
Which of the following metal is used for nuclear energy?
Uranium
Thorium
Niobium
All of these
Eutectoid reaction occurs at
600°C
723°C
1147°C
1493°C
The metal suitable for bearings subjected to light loads, is
Silicon bronze
White metal
Monel metal
Phosphor bronze