Which of the following is the binding material in cemented carbides?
Cobalt
Nickel
Vanadium
Iron
Correct Answer :
A. Cobalt
Related Questions
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
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
Malleable cast iron
Contains 1.7 to 3.5% carbon in Free State and is obtained by the slow cooling of molten cast iron
Is also known as chilled cast iron and is obtained by cooling rapidly. It is almost unmachinable
Is produced by annealing process. It is soft, tough, and easily machined metal
Is produced by small additions of magnesium (or cerium) in the ladle. Graphite is in the nodular or spheroidal form and is well dispersed throughout the material
Wrought iron
Is a ductile material
Can be easily forged or welded
Cannot stand sudden and excessive shocks
All of these
The aluminium alloy made by melting aluminium with 2 to 10% magnesium and 1.75% copper is called
Duralumin
Y-alloy
Magnalium
Hindalium
Tungsten in high speed steel provides
Hot hardness
Toughness
Wear resistance
Sharp cutting edge
In low carbon steels, ________ raises the yield point and improves the resistance to atmospheric corrosion.
Sulphur
Phosphorus
Manganese
Silicon
The percentage of carbon in grey iron castings usually varies between
0.5 to 1 %
1.2 %
2.5 to 4.5 %
5 to 7 %
The basic constituents of Hastelloy are
Aluminium, copper etc.
Nickel, molybdenum etc.
Nickel, Copper, etc.
All of the above
Which of the following material has nearly zero coefficient of expansion?
Stainless steel
High speed steel
Invar
Heat resisting steel
Bronze is an alloy of
Copper and zinc
Copper and tin
Copper, tin and zinc
None of these
In basic Bessemer process, the furnace is lined with
Silica bricks
A mixture of tar and burnt dolomite bricks
Both (A) and (B)
None of these
The carbon in the pig iron varies from
0.1 to 0.5 %
0.5 to 1 %
1 to 5 %
5 to 10 %
The percentage of carbon in low carbon steel is
0.05 %
0.15 %
0.3 %
0.5 %
The composition of silver solder is
Silver, copper, zinc
Silver, tin, nickel
Silver, lead, zinc
Silver, copper, aluminium
Nodular iron has
High machinability
Low melting point
High tensile strength
All of the above
In induction hardening ________ is high.
Current
Voltage
Frequency
Temperature
The heat treatment process used for softening hardened steel is
Carburising
Normalising
Annealing
Tempering
In full annealing, the hypo eutectoid steel is heated from 30°C to 50°C above the upper critical temperature and then cooled
In still air
Slowly in the furnace
Suddenly in a suitable cooling medium
Any one of these
The alloying element which can replace tungsten in high speed steels is
Nickel
Vanadium
Cobalt
Molybdenum
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
The alloying element which increases residual magnetism and coercive magnetic force in steel for magnets is
Chromium
Nickel
Vanadium
Cobalt
Maximum percentage of carbon in austenite is
0.025 %
0.26 %
0.8 %
1.7 %
The coke in the charge of blast furnace
Controls the grade of pig iron
Acts as an iron bearing mineral
Supplies heat to reduce ore and melt the iron
Forms a slag by combining with impurities
An alloy of copper, tin and zinc is known as
Brass
Bronze
Gun metal
Muntz metal
The ultimate tensile strength of low carbon steel by working at a high strain rate will
Decrease
Increase
Remain constant
First increase and then decrease
The type of space lattice found in gamma-iron is
Face centered cubic space lattice
Body centered cubic space lattice
Close packed hexagonal space lattice
None of these
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
Addition of copper to aluminium results in
Improvement of casting characteristics
Improvement of corrosion resistance
One of the best known age and precipitation hardening systems
Improving machinability
Nickel 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