The machinability of aluminium increases when __________ is added to aluminium.
Copper
Magnesium
Silicon
Lead and bismuth
Correct Answer :
D. Lead and bismuth
Related Questions
The presence of sulphur in pig iron makes
It easily machinable
It brittle
It hard
The casting unsound
The alloying element which can replace tungsten in high speed steels is
Nickel
Vanadium
Cobalt
Molybdenum
Inconel contains
65% nickel, 15% chromium and 20% iron
68% nickel, 29% copper and 3% other constituents
80% nickel and 20% chromium
80% nickel, 14% chromium and 6% iron
The most effective inhibitor of grain growth, when added in small quantities is
Carbon
Vanadium
Manganese
Cobalt
Which of the following pipes is least corrosion resistant?
Brass
Mild steel
Cast iron
Wrought iron
White cast iron has
Carbon in the form of carbide
Low tensile strength
High compressive strength
All of these
Which of the following is used for bearing liner?
Gun metal
Bronze
Bell metal
Babbitt metal
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
Steel with ________ carbon is known as hypo-eutectoid steel.
0.8 %
Below 0.8 %
Above 0.8 %
None of these
Which of the following statement is wrong?
Steel with 0.8% carbon is wholly pearlite
The amount of cementite increases with the increase in percentage of carbon in iron
A mechanical mixture of 87% cementite and 13% ferrite is called pearlite
The cementite is identified as round particles in the structure
The temperature required for full annealing in hypereutectoid steel is
30°C to 50°C above upper critical temperature
30°C to 50°C below upper critical temperature
30°C to 50°C above lower critical temperature
30°C to 50°C below lower critical temperature
The usual composition of a soldering alloy is
Tin, lead and small percentage of antimony
Tin and lead
Tin, lead and silver
Tin and copper
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
Which is false statement about normalizing? Normalizing is done to
Refine grain structure
Reduce segregation in casting
Improve mechanical properties
Induce stresses
The brown smoke during the operation of a Bessemer converter indicates that the
Air is burning out silicon and manganese
Silicon and manganese has burnt and carbon has started oxidising
The converter must be titled to remove the contents of the converter
The brown smoke does not occur during the operation of a Bessemer converter
Basic constituents of Monel metal are
Nickel, copper
Nickel, molybdenum
Zinc, tin, lead
Nickel, lead and tin
Ball bearings are, usually, made from
Low carbon steel
High carbon steel
Medium carbon steel
Chrome steel
Which of the following metal is used for nuclear energy?
Uranium
Thorium
Niobium
All of these
Delta metal is an alloy of
Copper, zinc and iron
Iron, nickel and copper
Iron, lead and tin
Iron, aluminium and magnesium
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
Babbitt metal is a
Lead base alloy
Copper base alloy
Tin base alloy
Cadmium base alloy
Taps dies and drills contain carbon
Below 0.5 %
Below 1 %
Above 1 %
Above 2.2 %
Nodular iron has
High machinability
Low melting point
High tensile strength
All of the above
Tungsten 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
Connecting rod is usually made of
Aluminium
Low carbon steel
Medium carbon steel
High carbon steel
1841 high speed steel contains
Vanadium 4%, chromium 18% and tungsten 1%
Vanadium 1%, chromium 4% and tungsten 18%
Vanadium 18%, chromium 1% and tungsten 4%
None of the above
Grey cast iron has
Carbon in the form of free graphite
High tensile strength
Low compressive strength
All of these
Inconel is an alloy of
Nickel, chromium and iron
Nickel, copper
Nickel, Chromium
Nickel, zinc
In nodular iron, graphite is in the form of
Cementite
Free carbon
Flakes
Spheroids
When low carbon steel is heated up to upper 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