In grey cast iron, carbon is present in the form of
Cementite
Free carbon
Flakes
Spheroids
Correct Answer :
C. Flakes
Related Questions
Which is false statement about tempering? Tempering is done to
Improve machinability
Improve ductility
Improve toughness
Release stresses
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
Mild steel belongs to the following category
Low carbon steel
Medium carbon steel
High carbon steel
Alloy steel
The crystal structure of gamma iron is
Body centered cubic
Face centred cubic
Hexagonal close packed
Cubic structure
Aluminium bronze contains aluminium and copper in the ratio of
50 : 50
40 : 60
60 : 40
10 : 90
The machinability of steel is improved by adding
Nickel
Chromium
Nickel and chromium
Sulphur, lead and phosphorus
Silicon when added to copper improves
Machinability
Hardness
Hardness and strength
Strength and ductility
Malleability of a material can be defined as
Ability to undergo large permanent deformations in compression
Ability to recover its original form
Ability to undergo large permanent deformations in tension
All of the above
A reversible change in the atomic structure of the steel with a corresponding change in the properties is known as
Allotropic change
Recrystallisation
Heat treatment
Precipitation
The material widely used for making pendulums of clocks is
Stainless steel
High speed steel
Heat resisting steel
Nickel steel
Amorphous material is one
In which atoms align themselves in a geometric pattern upon solidification
In which there is no definite atomic structure and atoms exist in a random pattern just as in a liquid
Which is not attacked by phosphorous
Which emits fumes on melting
Blast furnace is used to produce
Pig iron
Cast iron
Wrought iron
Steel
Age-hardening is related with
Stainless steel
Gun metal
German silver
Duralumin
German silver contains
1% silver
2.5% silver
5% silver
10% silver
Which of the following property is desirable for materials used in tools and machines?
Elasticity
Plasticity
Ductility
Malleability
Maximum percentage of carbon in ferrite is
0.025 %
0.06 %
0.1 %
0.25 %
Which of the following when used in ordinary low carbon steels, makes the metal ductile and of good bending qualities?
Sulphur
Phosphorus
Manganese
Silicon
The blade of a power saw is made of
Boron steel
High speed steel
Stainless steel
Malleable cast iron
German silver is an alloy of
Silver and some impurities
Refined silver
Nickel, Copper and zinc
Nickel and copper
Which of the following property is desirable in parts subjected to shock and impact loads?
Strength
Stiffness
Brittleness
Toughness
Heavy duty leaf and coil springs contain carbon of the following order
0.2 %
0.5 %
0.8 %
1.0 %
Weld decay is the phenomenon found with
Cast iron
Mild steel
Nonferrous materials
Stainless steel
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
The alloy, mainly used for corrosion resistance in stainless steels is
Silicon
Manganese
Carbon
Chromium
Iron-carbon alloys containing carbon ________ 4.3% are known as hypereutectic cast irons.
Equal to
Less than
More than
None of these
Gamma-iron occurs between the temperature ranges of
400°C to 600°C
600°C to 900°C
900°C to 1400°C
1400°C to 1530°C
Which of the following steel making process is being adopted at Rourkela (in India) Steel Plant?
Bessemer process
Open hearth process
Electric process
LD process
Wrought iron is
Hard
High in strength
Highly resistant to corrosion
Heat treated to change its properties
The hardness is the property of a material due to which it
Can be drawn into wires
Breaks with little permanent distortion
Can cut another metal
Can be rolled or hammered into thin sheets
Basic constituents of Monel metal are
Nickel, copper
Nickel, molybdenum
Zinc, tin, lead
Nickel, lead and tin