Pick up wrong statement about wrought iron
It contains carbon of the order of 0 to 0.25%
It melts at 1535°C
It is very soft and ductile
It is made by adding suitable percentage of carbon to molten iron and subjecting the product to repeated hammering and rolling.
Correct Answer :
D. It is made by adding suitable percentage of carbon to molten iron and subjecting the product to repeated hammering and rolling.
Related Questions
Wrought iron is
Hard
High in strength
Highly resistant to corrosion
Heat treated to change its properties
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
Ductility 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
The hardness and tensile strength in austenitic stainless steel can be increased by
Hardening and cold working
Normalising
Martempering
Full annealing
The silicon steel is widely used for
Connecting rods
Cutting tools
Generators and transformers in the form of laminated cores
Motor car crankshafts
By severely deforming a metal in a particular direction it becomes
Ductile
Malleable
Homogeneous
Anisotropic
A material is known as allotropic or polymorphic if it
Has a fixed structure under all conditions
Exists in several crystal forms at different temperatures
Responds to heat treatment
Has its atoms distributed in a random pattern
When the steel is normalised, its
Yield point increases
Ductility decreases
Ultimate tensile strength increases
All of these
The addition of which of the following improves machining of copper?
Sulphur
Vanadium
Tin
Zinc
Super conduction by metals is observed in the temperature range of
Below 10°K
Above 100°K
Around 0°C
Around 100°C
Which is false statement about normalizing? Normalizing is done to
Refine grain structure
Reduce segregation in casting
Improve mechanical properties
Induce stresses
The elastic stress strain behaviour of rubber is
Linear
Nonlinear
Plastic
No fixed relationship
Brass contains
70% copper and 30% zinc
90% copper and 10% tin
85 - 92% copper and rest tin with little lead and nickel
70 - 75% copper and rest tin
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
Tin base white metals are used where the bearings are subjected to
Large surface wear
Elevated temperatures
Light load and pressure
High pressure and load
The crystal structure of brass is
F.C.C.
B.C.C.
H.C.P.
Orthorhombic crystalline structure
Basic constituents of Monel metal are
Nickel, copper
Nickel, molybdenum
Zinc, tin, lead
Nickel, lead and tin
The alloy used for making electrical resistances and heating elements is
Nichrome
Invar
Magnin
Elinvar
The temperature required for full annealing in hypereutectoid steel is
30°C to 50°C above upper critical temperature
30°C to 50°C below upper critical temperature
30°C to 50°C above lower critical temperature
30°C to 50°C below lower critical temperature
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
Cast iron is manufactured in
Blast furnace
Cupola
Open hearth furnace
Bessemer converter
Shock resistance of steel is increased by adding
Nickel
Chromium
Nickel and chromium
Sulphur, lead and phosphorus
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
Acidic 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
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
Stress relaxation is the phenomenon
In which parts are not loaded
In which stress remains constant on increasing load
In which deformation tends to loosen the joint and produces a stress reduced
Stress reduces on increasing load
The unique property of cast iron is its high
Malleability
Ductility
Surface finish
Damping characteristics
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
The electric process of steel making is especially adapted to
Alloy and carbon tool steel
Magnet steel
High speed tool steel
All of these