Which of the following metal is used in making electrical resistance wire for electric furnaces and heating elements?
Babbitt metal
Monel metal
Nichrome
Phosphor bronze
Correct Answer :
C. Nichrome
Related Questions
Argentite is the principal ore or raw material for
Aluminium
Tin
Zinc
Silver
Which of the following statement is incorrect about duralumin?
It is prone to age hardening
It can be forged
It has good machining properties
It is lighter than pure aluminium
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
Manganese in steel increases its
Tensile strength
Hardness
Ductility
Fluidity
Thermoplastic materials are those materials which
Are formed into shape under heat and pressure and results in a permanently hard product
Do not become hard with the application of heat and pressure and no chemical change occurs
Are flexible and can withstand considerable wear under suitable conditions
Are used as a friction lining for clutches and brakes
Chilled cast iron has
No graphite
A very high percentage of graphite
A low percentage of graphite
Graphite as its basic constituent of composition
Railway rails are normally made of
Mild steel
Alloy steel
High carbon
Tungsten steel
Paramagnetic alpha iron changes to gamma iron at
770°C
910°C
1440°C
1539°C
Nickel when added to copper improves
Machinability
Hardness
Hardness and strength
Strength and ductility
Pearlite consists of
13% carbon and 87% ferrite
13% cementite and 87% ferrite
13% ferrite and 87% cementite
6.67% carbon and 93.33% iron
Induction hardening is basically a
Carburising process
Surface hardening process
Core hardening process
None of these
Iron ore is, usually, found in the form of
Oxides
Carbonates
Sulphides
All of these
'Killed steels' are those steels
Which are destroyed by burning
Which after their destruction are recycled to produce fresh steel
Which are deoxidised in the ladle with silicon and aluminium
In which carbon is completely burnt
Which is the false statement about wrought iron? It has
High resistance to rusting and corrosion
High ductility
Ability of hold protective coating
Uniform strength in all directions
Aluminium bronze contains aluminium and copper in the ratio of
50 : 50
40 : 60
60 : 40
10 : 90
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 steel widely used for motor car crankshafts is
Nickel steel
Chrome steel
Nickel-chrome steel
Silicon steel
In compression, a prism of brittle material will break
By forming a bulge
By shearing along oblique plane
In direction perpendicular to application of load
By crushing into thousands of pieces
Which of the following elements does not impart hardness to steel?
Copper
Chromium
Nickel
Silicon
The tensile strength of wrought iron is maximum
Along the lines of slag distribution
Perpendicular to lines of slag distribution
Uniform in all directions
None of the above
Monel metal is an alloy of
Nickel and copper
Nickel and chromium
Nickel, Chromium and iron
Copper and chromium
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
Grey 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 is obtained by cooling rapidly. It is almost unmachinable
Is produced by annealing process. I is soft, tough and easily machined metal
Is produced by small additions o magnesium (or cerium) in the ladle Graphite is in nodular or spheroidal form and is well dispersed throughout the material
The alloy used for making electrical resistances and heating elements is
Nichrome
Invar
Magnin
Elinvar
Shock resisting steels should have
Low wear resistance
Low hardness
Low tensile strength
Toughness
Mild steel belongs to the following category
Low carbon steel
Medium carbon steel
High carbon steel
Alloy steel
The metallic structure of mild steel is
Body centred cubic
Face centred cubic
Hexagonal close packed
Cubic structure
Cast iron has
High tensile strength
Its elastic limit close to the ultimate breaking strength
High ductility
All of the above
Balls for ball bearings are made of
Cast iron
Mild steel
Stainless steel
Carbonchrome steel
Tungsten when added to steel ________ the critical temperature.
Does not effect
Lowers
Raises
None of these