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
Correct Answer :
B. 50% or more iron
Related Questions
The material in which the atoms are arranged chaotically, is called
Amorphous material
Mesomorphous material
Crystalline material
None of these
An engineer's hammer is made of
Cast iron
Forged steel
Mild steel
High carbon steel
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 %
Iron ore is, usually, found in the form of
Oxides
Carbonates
Sulphides
All of these
Which of the following has a fine gold colour and is used for imitation jewellery?
Silicon bronze
Aluminium bronze
Gun metal
Babbitt metal
Which of the following statements are true for annealing of steels?
Steels are heated to 500 to 700°C
Cooling is done slowly and steadily
Internal stresses are relieved
All of these
Silicon when added to copper improves
Machinability
Hardness
Hardness and strength
Strength and ductility
Steel containing ferrite and pearlite is
Hard
Soft
Tough
Hard and tough
The machinability of steel is improved by adding
Nickel
Chromium
Nickel and chromium
Sulphur, lead and phosphorus
Hardness of steel depends on
Amount of carbon it contains
The shape and distribution of the carbides in iron
Method of fabrication
Contents of alloying elements
In mottled cast iron, carbon is available in
Free form
Combined form
Nodular form
Partly in free and partly in combined state
Manganese in steel increases its
Tensile strength
Hardness
Ductility
Fluidity
Basic solution is one which has pH value
Greater than 7
Equal to 7
Less than 7
pH value has nothing to do with basic solution
The ratio of the volume occupied by the atoms to the total volume of the unit cell is called
Coordination number
Atomic packing factor
Space lattice
None of these
Babbitt metal is a
Lead base alloy
Tin base alloy
Copper base alloy
Both (A) and (C) above
Isotropic materials are those which have the same
Elastic properties in all directions
Stresses induced in all directions
Thermal properties in all directions
Electric and magnetic properties in all directions
Which one of the following metals would work-harden more quickly than the others?
Copper
Brass
Lead
Silver
The strength is the ability of a material to resist
Deformation under stress
Externally applied forces with breakdown or yielding
Fracture due to high impact loads
None of these
White cast iron contains carbon in the form of
Free carbon
Graphite
Cementite
White carbon
Which of the following element results in presence of free graphite in C.I.?
Carbon
Sulphur
Silicon
Manganese
According to Indian standard specifications, SG 400/15 means
Spheroidal graphite cast iron with B.H.N. 400 and minimum tensile strength 15 MPa
Spheroidal graphite cast iron with minimum tensile strength 400 MPa and 15 percent elongation
Spheroidal graphite cast iron with minimum compressive strength 400 MPa and 15 percent reduction in area
None of the above
When elements like nickel, chromium, copper and molybdenum are added to the molten cast iron, it produces
White cast iron
Nodular cast iron
Malleable cast iron
Alloy cast iron
In which of the following cases, consideration of creep is important
Flywheel of steam engine
Cast iron pipes
Cycle chains
Gas turbine blades
Melting point of iron is
1539°C
1601°C
1489°C
1712°C
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
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
Which of the following when used in ordinary low carbon steels, makes the metal ductile and of good bending qualities?
Sulphur
Phosphorus
Manganese
Silicon
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