The main alloying elements high speed steel in order of increasing proportion are
Vanadium, chromium, tungsten
Tungsten, titanium, vanadium
Chromium, titanium, vanadium
Tungsten, chromium, titanium
Correct Answer :
A. Vanadium, chromium, tungsten
Related Questions
Amorphous material is one
In which atoms align themselves in a geometric pattern upon solidification
In which there is no definite atomic structure and atoms exist in a random pattern just as in a liquid
Which is not attacked by phosphorous
Which emits fumes on melting
The crystal structure of brass is
F.C.C.
B.C.C.
H.C.P.
Orthorhombic crystalline structure
The charge of the blast furnace consists of
Calcined ore (8 parts), coke (4 parts) and limestone (1 part)
Calcined ore (4 parts), coke (1 part) and limestone (8 parts)
Calcined ore (1 part), coke (8 parts) and limestone (4 parts)
Calcined ore, coke and limestone all in equal parts
In low carbon steels, presence of small quantities of sulphur improves
Weldability
Formability
Machinability
Hardenability
In which of the following cases, consideration of creep is important
Flywheel of steam engine
Cast iron pipes
Cycle chains
Gas turbine blades
Body centered cubic space lattice is found in
Zinc, magnesium, cobalt, cadmium, antimony and bismuth
Gamma iron, aluminium, copper, lead, silver and nickel
Alpha iron, tungsten, chromium and molybdenum
None of the above
Pick up wrong statement about wrought iron
It contains carbon of the order of 0 to 0.25%
It melts at 1535°C
It is very soft and ductile
It is made by adding suitable percentage of carbon to molten iron and subjecting the product to repeated hammering and rolling.
Which of the following is an amorphous material?
Mica
Silver
Lead
Glass
Solder is an alloy consisting of
Tin, antimony, copper
Tin and copper
Tin and lead
Lead and zinc
Which of the following element results in presence of free graphite in C.I.?
Carbon
Sulphur
Silicon
Manganese
Iron is
Paramagnetic
Ferromagnetic
Ferroelectric
Dielectric
Which of the following is added in low carbon steels to prevent them from becoming porous?
Sulphur
Phosphorus
Manganese
Silicon
Muntz metal contains copper and zinc in the ratio of
50 : 50
40 : 60
60 : 40
20 : 80
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
A reversible change in the atomic structure of the steel with a corresponding change in the properties is known as
Allotropic change
Recrystallisation
Heat treatment
Precipitation
Dow metal contains
94% aluminium, 4% copper and 0.5% Mn, Mg, Si and Fe
92.5% aluminium and, 4% copper, 2% nickel and 1.5% Mg
90% aluminium and 90% copper
90% magnesium and 9% aluminium with some copper
The steel widely used for motor car crankshafts is
Nickel steel
Chrome steel
Nickel-chrome steel
Silicon steel
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
Steel made from phosphate iron is
Brittle
Hard
Ductile
Tough
Induction hardening is the process of
Hardening surface of work-piece to obtain hard and wear resistant surface
Heating and cooling rapidly
Increasing hardness throughout
Inducing hardness by continuous process
Chromium when added to steel __________ the tensile strength.
Does not effect
Decreases
Increases
None of these
Preheating is essential in welding
Cast iron
High speed steel
All nonferrous materials
All of the above
Ductile 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 creium) in the ladle. Graphite is in nodular or spheroidal form and is well dispersed throughout the material
Manganese in steel increases its
Tensile strength
Hardness
Ductility
Fluidity
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
Materials after cold working are subjected to following process to relieve stresses
Hot working
Tempering
Normalising
Annealing
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
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
For a steel containing 0.8% carbon
There is no critical point
There is only one critical point
There are two critical points
There can be any number of critical points
Following elements have face-centred cubic structure
Gamma iron (910° to 1400°C), Cu, Ag, Au, Al, Ni, Pb, Pt
Mg, Zn, Ti, Zr, Br, Cd
A iron (below 910°C and between 1400 to 1539°C), W
All of the above