Which of the following impurity in cast iron makes it hard and brittle?
Silicon
Sulphur
Manganese
Phosphorus
Correct Answer :
B. Sulphur
Related Questions
The composition of silver solder is
Silver, copper, zinc
Silver, tin, nickel
Silver, lead, zinc
Silver, copper, aluminium
Elinvar, an alloy used in precision instruments, hair springs for watches, etc. contains the following element as principal alloying element
Iron
Copper
Aluminium
Nickel
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
The lower critical temperature
Decreases as the carbon content in steel increases
Increases as the carbon content in steel increases
Is same for all steels
Depends upon the rate of heating
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
Which of the following elements does not impart hardness to steel?
Copper
Chromium
Nickel
Silicon
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
Aluminium bronze contains aluminium and copper in the ratio of
50 : 50
40 : 60
60 : 40
10 : 90
The cupola is used to manufacture
Pig iron
Cast iron
Wrought iron
Steel
Depth of hardness of steel is increased by addition of
Nickel
Chromium
Tungsten
Vanadium
Connecting rod is usually made of
Aluminium
Low carbon steel
Medium carbon steel
High carbon steel
Nimonic contains __________ percentage of nickel as that of Inconel.
Same
Less
More
None of these
The transistor is made of
Silver
Gold
Copper
Germanium
Silicon when added to copper improves
Machinability
Hardness
Hardness and strength
Strength and ductility
Free carbon in iron makes the metal
Soft and gives a coarse grained crystalline structure
Soft and gives a fine grained crystalline structure
Hard and gives a coarse grained crystalline structure
Hard and gives a fine grained crystalline structure
Iron is
Paramagnetic
Ferromagnetic
Ferroelectric
Dielectric
The machinability of aluminium increases when __________ is added to aluminium.
Copper
Magnesium
Silicon
Lead and bismuth
Muntz metal contains copper and zinc in the ratio of
50 : 50
40 : 60
60 : 40
20 : 80
Which one of the following metals would work-harden more quickly than the others?
Copper
Brass
Lead
Silver
Which of the following is used for bearing liner?
Gun metal
Bronze
Bell metal
Babbitt metal
Which of the following pipes is least corrosion resistant?
Brass
Mild steel
Cast iron
Wrought iron
Ductility 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
Cast iron is manufactured in
Blast furnace
Cupola
Open hearth furnace
Bessemer converter
Structural steel contains following principal alloying elements
Nickel, chromium and manganese
Tungsten, molybdenum and phosphorous
Lead, tin, aluminium
Zinc, sulphur, and chromium
Stress relaxation is the phenomenon
In which parts are not loaded
In which stress remains constant on increasing load
In which deformation tends to loosen the joint and produces a stress reduced
Stress reduces on increasing load
Tin base white metals are used where the bearings are subjected to
Large surface wear
Elevated temperatures
Light load and pressure
High pressure and load
Which of the following material has nearly zero coefficient of expansion?
Stainless steel
High speed steel
Invar
Heat resisting steel
Age-hardening is related with
Stainless steel
Gun metal
German silver
Duralumin
Austenite is a combination of
Ferrite and cementite
Cementite and gamma iron
Ferrite and austenite
Ferrite and iron graphite
The temperature at which ferromagnetic alpha iron transforms to paramagnetic alpha iron is
770°C
910°C
1050°C
Below recrystallisation temperature