Which is false statement about annealing? Annealing is done to
Relieve stresses
Harden steel slightly
Improve machining characteristic
Soften material
Correct Answer :
B. Harden steel slightly
Related Questions
The charge of the blast furnace consists of
Calcined ore (8 parts), coke (4 parts) and limestone (1 part)
Calcined ore (4 parts), coke (1 part) and limestone (8 parts)
Calcined ore (1 part), coke (8 parts) and limestone (4 parts)
Calcined ore, coke and limestone all in equal parts
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
Slow plastic deformation of metals under a constant stress is known as
Creep
Fatigue
Endurance
Plastic deformation
Which of the following metal shrinks most from molten state to solid state?
Cast iron
Cast steel
Brass
Admiralty metal
Following elements have face-centred cubic structure
Gamma iron (910° to 1400°C), Cu, Ag, Au, Al, Ni, Pb, Pt
Mg, Zn, Ti, Zr, Br, Cd
A iron (below 910°C and between 1400 to 1539°C), W
All of the above
In low carbon steels, ________ raises the yield point and improves the resistance to atmospheric corrosion.
Sulphur
Phosphorus
Manganese
Silicon
In high speed steels, manganese is used to tougher the metal and to increase its
Yield point
Critical temperature
Melting point
Hardness
The type of space lattice found in alpha-iron is
Face centred cubic space lattice
Body centred cubic space lattice
Close packed hexagonal space lattice
None of these
Depth of hardness of steel is increased by addition of
Nickel
Chromium
Tungsten
Vanadium
The metal suitable for bearings subjected to heavy loads, is
Silicon bronze
White metal
Monel metal
Phosphor bronze
The alloy used for making electrical resistances and heating elements is
Nichrome
Invar
Magnin
Elinvar
Manganese in steel increases its
Tensile strength
Hardness
Ductility
Fluidity
The toughness of a material __________ when it is heated.
Remain same
Decreases
Increases
None of these
Cemented carbide tools are not found to be suitable for cutting
Brass
Cast iron
Aluminium
Steel
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
In induction hardening ________ is high.
Current
Voltage
Frequency
Temperature
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
Addition of manganese to aluminium results in
Improvement of casting characteristics
Improvement of corrosion resistance
One of the best known age and precipitation hardening systems
Improving machinability
The property of a material due to which it breaks with little permanent distortion, is called
Brittleness
Ductility
Malleability
Plasticity
The cupola is used to manufacture
Pig iron
Cast iron
Wrought iron
Steel
A steel containing 16 to 18% chromium and about 0.12% carbon is called
Ferritic stainless steel
Austenitic stainless steel
Martenistic stainless 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
Pure iron is the structure of
Ferrite
Pearlite
Austenite
Ferrite and cementite
Macrostructure of a material is, generally, examined by
Naked eye
Optical microscope
Metallurgical microscope
X-ray techniques
An engineer's hammer is made of
Cast iron
Forged steel
Mild steel
High carbon steel
Eutectoid steel contains following percentage of carbon
0.02 %
0.3 %
0.63 %
0.8 %
The percentage of carbon in low carbon steel is
0.05 %
0.15 %
0.3 %
0.5 %
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 unique property of cast iron is its high
Malleability
Ductility
Surface finish
Damping characteristics
In which of the following cases, consideration of creep is important
Flywheel of steam engine
Cast iron pipes
Cycle chains
Gas turbine blades