Duralumin contains
3.5 to 4.5% copper, 0.4 to 0.7% magnesium, 0.4 to 0.7% manganese and rest aluminium
3.5 to 4.5% copper, 1.2 to 1.7% manganese, 1.8 to 2.3% nickel, 0.6% each of silicon, magnesium and iron, and rest aluminium
4 to 4.5% magnesium, 3 to 4% copper and rest aluminium
5 to 6% tin, 2 to 3% copper and rest aluminium
Correct Answer :
A. 3.5 to 4.5% copper, 0.4 to 0.7% magnesium, 0.4 to 0.7% manganese and rest aluminium
Related Questions
The percentage of carbon in cast iron varies from
0.1 to 0.5
0.5 to 1
1 to 1.7
1.7 to 4.5
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
Brass contains
70% copper and 30% zinc
90% copper and 10% tin
85 - 92% copper and rest tin with little lead and nickel
70 - 75% copper and rest tin
The hardness of steel increases if it contains
Austenite
Martensite
Pearlite
Cementite
Solder is an alloy consisting of
Tin, antimony, copper
Tin and copper
Tin and lead
Lead and zinc
The ultimate tensile strength and yield strength of most of the metals, when temperature falls from 0 to 100°C will
Increase
Decrease
Remain same
First increase and then decrease
Duralumin contains
3.5 to 4.5% copper, 0.4 to 0.7% magnesium, 0.4 to 0.7% manganese and rest aluminium
3.5 to 4.5% copper, 1.2 to 1.7% manganese, 1.8 to 2.3% nickel, 0.6% each of silicon, magnesium and iron, and rest aluminium
4 to 4.5% magnesium, 3 to 4% copper and rest aluminium
5 to 6% tin, 2 to 3% copper and rest aluminium
Surveying tapes are made of a material having low coefficient of expansion and enough strength. The alloy used is
Silver metal
Duralumin
Hastelloy
Invar
The alloying element which reduces the formation of iron sulphide in steel is
Chromium
Nickel
Vanadium
Manganese
Which of the following represents the allotropic forms of iron?
Alpha iron, beta iron and gamma iron
Alpha iron and beta iron
Body centred cubic iron and face centred cubic iron
Alpha iron, gamma from and delta iron
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
Acidic solution is one which has pH value
Greater than 7
Less than 7
Equal to 7
pH value has nothing to do with neutral solution
Melting point of iron is
1539°C
1601°C
1489°C
1712°C
Brass (alloy of copper and zinc) is an example of
Substitutional solid solution
Interstitial solid solution
Intermetallic compounds
All of the above
Smelting is the process of
Removing the impurities like clay, sand etc. from the iron ore by washing with water
Expelling moisture, carbon dioxide, sulphur and arsenic from the iron ore by heating in shallow kilns
Reducing the ore with carbon in the presence of a flux
All of the above
Taps dies and drills contain carbon
Below 0.5 %
Below 1 %
Above 1 %
Above 2.2 %
An alloy of copper, tin and zinc is known as
Brass
Bronze
Gun metal
Muntz metal
Chilled cast iron has
No graphite
A very high percentage of graphite
A low percentage of graphite
Graphite as its basic constituent of composition
Age hardening is related to
Duralumin
Brass
Copper
Silver
Which is false statement about properties of aluminium?
Modulus of elasticity is fairly low
Wear resistance is very good
Fatigue strength is not high
Creep strength limits its use to fairly low temperatures
A specimen of aluminium metal when observed under microscope shows
B.C.C. crystalline structure
F.C.C. crystal structure
H.C.P. structure
A complex cubic structure
Weld decay is the phenomenon found with
Cast iron
Mild steel
Nonferrous materials
Stainless steel
The temperature at which ferromagnetic alpha iron transforms to paramagnetic alpha iron is
770°C
910°C
1050°C
Below recrystallisation temperature
Gun metal contains
70% copper and 30% zinc
90% copper and 10% tin
85 - 92% copper and rest tin with little lead and nickel
70 - 78% copper and rest tin
The addition of which of the following improves machining of copper?
Sulphur
Vanadium
Tin
Zinc
Which of the following pipes is least corrosion resistant?
Brass
Mild steel
Cast iron
Wrought iron
Carbon in iron is an example of
Substitutional solution
Interstitial solid solution
Intermetallic compounds
All of the above
Induction hardening is basically a
Carburising process
Surface hardening process
Core hardening process
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 %
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