Eutectoid steel consists of
Wholly pearlite
Wholly austenite
Pearlite and ferrite
Pearlite and cementite
Correct Answer :
A. Wholly pearlite
Related Questions
Phosphor bronze contains
0.5% of phosphorous
1% phosphorous
2.5% phosphorous
None of the above
The correct sequence for descending order of machinability is
Grey cast iron, low carbon steel, wrought iron
Low carbon steel, grey cast iron, wrought iron
Wrought iron, low carbon steel, grey cast iron
Wrought iron, grey cast iron, low carbon steel
Which of the following is added in low carbon steels to prevent them from becoming porous?
Sulphur
Phosphorus
Manganese
Silicon
Wrought iron is
Hard
High in strength
Highly resistant to corrosion
Heat treated to change its properties
Lead is poured into the joint between two pipes. These pipes may be made of
Cast iron
Vitrified clay
Asbestos cement
Concrete
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
Which is the false statement about wrought iron? It has
High resistance to rusting and corrosion
High ductility
Ability of hold protective coating
Uniform strength in all directions
The basic constituents of Hastelloy are
Aluminium, copper etc.
Nickel, molybdenum etc.
Nickel, Copper, etc.
All of the above
Which is false statement about case hardening? Case hardening is done by
Electroplating
Cyaniding
Induction hardening
Nitriding
Pure iron is the structure of
Ferrite
Pearlite
Austenite
Ferrite and cementite
Basic constituents of Monel metal are
Nickel, copper
Nickel, molybdenum
Zinc, tin, lead
Nickel, lead and tin
Which of the following metal shrinks most from molten state to solid state?
Cast iron
Cast steel
Brass
Admiralty metal
Crystal structure of a material is, generally, examined by
Naked eye
Optical microscope
Metallurgical microscope
X-ray techniques
Weld decay is the phenomenon found with
Cast iron
Mild steel
Nonferrous materials
Stainless steel
Which of the following display properties similar to that of steel?
Blackheart cast iron
White-heart cast iron
Both (A) and (B)
None of these
Vanadium in high speed steels
Promotes decarburisation
Provides high hot hardness
Forms very hard carbides and thus increases wear resistance
Promotes retention of austenite
The aluminium alloy made by melting aluminium with 2 to 10% magnesium and 1.75% copper is called
Duralumin
Y-alloy
Magnalium
Hindalium
In compression, a prism of brittle material will break
By forming a bulge
By shearing along oblique plane
In direction perpendicular to application of load
By crushing into thousands of pieces
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
Chromium in steel
Improves wear resistance, cutting ability and toughness
Refines grain size and produces less tendency to carburisation, improves corrosion and heat resistant properties
Improves cutting ability and reduces hardenability
Gives ductility, toughness, tensile strength and anticorrosion properties
Iron-carbon alloys containing 1.7 to 4.3% carbon are known as
Eutectic cast irons
Hypoeutectic cast irons
Hypereutectic cast irons
None of these
The surface hardness of the following order is achieved by nitriding operation
600 VPN
1500 VPN
1000 to 1100 VPN
250 VPN
When filing or machining cast iron makes our hands black, then it shows that ________ is present in cast iron.
Cementite
Free graphite
Both A and B
None of these
The metallic structure of mild steel is
Body centred cubic
Face centred cubic
Hexagonal close packed
Cubic structure
The compressive strength of cast iron is ________ that of its tensile strength.
Equal to
Less than
More than
None of these
Shock resisting steels should have
Low wear resistance
Low hardness
Low tensile strength
Toughness
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
Babbitt metal is a
Lead base alloy
Copper base alloy
Tin base alloy
Cadmium base alloy
Tungsten in high speed steel provides
Hot hardness
Toughness
Wear resistance
Sharp cutting edge
Elinvar, an alloy used in precision instruments, hair springs for watches, etc. contains the following element as principal alloying element
Iron
Copper
Aluminium
Nickel