The alloying element which can replace tungsten in high speed steels is
Nickel
Vanadium
Cobalt
Molybdenum
Correct Answer :
D. Molybdenum
Related Questions
Cast iron has
High tensile strength
Its elastic limit close to the ultimate breaking strength
High ductility
All of the above
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
Aluminium bronze contains aluminium and copper in the ratio of
50 : 50
40 : 60
60 : 40
10 : 90
A reversible change in the atomic structure of steel with corresponding change in the properties is known as
Molecular change
Physical change
Allotropic change
Solidus change
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 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 impurity in cast iron makes it hard and brittle?
Silicon
Sulphur
Manganese
Phosphorus
Crystal structure of a material is, generally, examined by
Naked eye
Optical microscope
Metallurgical microscope
X-ray techniques
Free cutting steels
Contain carbon in free from
Require minimum cutting force
Is used where rapid machining is the prime requirement
Can be cut freely
Which of the following material has maximum ductility?
Mild steel
Copper
Nickel
Aluminium
The electric process of steel making is especially adapted to
Alloy and carbon tool steel
Magnet steel
High speed tool steel
All of these
Steel contains
80% or more iron
50% or more iron
Alloying elements like chromium, tungsten nickel and copper
Elements like phosphorus, sulphur and silicon in varying quantities
The metallic structure of mild steel is
Body centred cubic
Face centred cubic
Hexagonal close packed
Cubic structure
The ability of a material to resist softening at high temperature is known as
Creep
Hot tempering
Hot hardness
Fatigue
Which is false statement about annealing? Annealing is done to
Relieve stresses
Harden steel slightly
Improve machining characteristic
Soften material
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
Maximum percentage of carbon in austenite is
0.025 %
0.26 %
0.8 %
1.7 %
The alloy used for making electrical resistances and heating elements is
Nichrome
Invar
Magnin
Elinvar
White metal contains
63 to 67% nickel and 30% copper
88% copper and 10% tin and rest zinc
Alloy of tin, lead and cadmium
Silver and chromium
Cast iron is a
Ductile material
Malleable material
Brittle material
Tough material
When steel containing less than 0.8% carbon is cooled slowly from temperatures above or within the critical range, it consists of
Mainly ferrite
Mainly pearlite
Ferrite and pearlite
Pearlite and cementite
Steel with ________ carbon is known as hypo-eutectoid steel.
0.8 %
Below 0.8 %
Above 0.8 %
None of these
Which of the following is used for bearing liner?
Gun metal
Bronze
Bell metal
Babbitt metal
The basic constituents of Hastelloy are
Aluminium, copper etc.
Nickel, molybdenum etc.
Nickel, Copper, etc.
All of the above
Argentite is the principal ore or raw material for
Aluminium
Tin
Zinc
Silver
Specify the sequence correctly
Grain growth, recrystallisation, stress relief
Stress relief, grain growth, recrystallisation
Stress relief, recrystallisation, grain growth
Grain growth, stress relief, recrystallisation
In process annealing, the hypo eutectoid steel is
Heated from 30°C to 50°C above the upper critical temperature and then cooled in still air
Heated from 30°C to 50°C above the upper critical temperature and then cooled suddenly in a suitable cooling medium
Heated from 30°C to 50°C above the upper critical temperature and then cooled slowly in the furnace
Heated below or closes to the lower critical temperature and then cooled slowly
Super conduction by metals is observed in the temperature range of
Below 10°K
Above 100°K
Around 0°C
Around 100°C
Pipes for bicycle frames are made of
Cold rolled steel
Hot rolled steel
Forged steel
Cast steel
If a refractory contains high content of silicon, it means refractory is
Acidic
Basic
Neutral
Brittle