Preheating is essential in welding
Cast iron
High speed steel
All nonferrous materials
All of the above
Correct Answer :
A. Cast iron
Related Questions
Shock resisting steels should have
Low wear resistance
Low hardness
Low tensile strength
Toughness
The metal suitable for bearings subjected to light loads, is
Silicon bronze
White metal
Monel metal
Phosphor bronze
Which of the following alloys does not have copper as one of the constituents?
Delta metal
Monel metal
Constantan
Nichrome
Age-hardening is related with
Stainless steel
Gun metal
German silver
Duralumin
Quenching is not necessary when hardening is done by
Case hardening
Flame hardening
Nitriding
Any one of these
The unit cells
Contain the smallest number of atoms which when taken together have all the properties of the crystals of the particular metal
Have the same orientation and their similar faces are parallel
May be defined as the smallest parallelepiped which could be transposed in three coordinate directions to build up the space lattice
All of the above
German silver is an alloy of
Silver and some impurities
Refined silver
Nickel, Copper and zinc
Nickel and copper
Permalloy is a
Kind of stainless steel
None ferrous alloy
Polymer
Nickel and iron alloy having high permeability
Tungsten when added to steel ________ the critical temperature.
Does not effect
Lowers
Raises
None of these
Hardness of lower bainite (tempered martensite) is about
RC 65
RC 48
RC 57
RC 80
Maximum percentage of carbon in ferrite is
0.025 %
0.06 %
0.1 %
0.25 %
Which of the following display properties similar to that of steel?
Blackheart cast iron
White-heart cast iron
Both (A) and (B)
None of these
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
Malleable 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 cerium) in the ladle. Graphite is in the nodular or spheroidal form and is well dispersed throughout the material
Austenite is a combination of
Ferrite and cementite
Cementite and gamma iron
Ferrite and austenite
Ferrite and iron graphite
Steel made from phosphate iron is
Brittle
Hard
Ductile
Tough
The lower critical point for all steels is
600°C
700°C
723°C
913°C
Admiralty brass used for steam condenser tubes contains copper and zinc in the following ratio
50 : 50
30 : 70
70 : 30
40 : 60
Phosphor bronze contains
0.5% of phosphorous
1% phosphorous
2.5% phosphorous
None of the above
Which of the following is used for bearing liner?
Gun metal
Bronze
Bell metal
Babbitt metal
Pick up the wrong statement Nickel and chromium in steel help in
Providing corrosion resistance
Improving machining properties
Providing high strength at elevated temperatures
Raising the elastic limit
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
Inconel is an alloy of
Nickel, chromium and iron
Nickel, copper
Nickel, Chromium
Nickel, zinc
Sulphur in pig iron tends to make it
Hard
Soft
Ductile
Tough
Tungsten in high speed steel provides
Hot hardness
Toughness
Wear resistance
Sharp cutting edge
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
Ferromagnetic alpha iron exists in temperature range of
Below 723°C
770 to 910°C
910 to 1440°C
1400 to 1539°C
Delta-iron occurs between the temperature ranges of
400°C to 600°C
600°C to 900°C
900°C to 1400°C
1400°C to 1530°C
The following types of materials are usually the most ductile
Face centred cubic lattice
Body centred cubic lattice
Hexagonal close packed lattice
All of the above
Pick up the wrong statement
Aluminium in steel results in excessive grain growth
Manganese in steel induces hardness
Nickel and chromium in steel helps in raising the elastic limit and improve the resilience and ductility
Tungsten in steels improves magnetic properties and hardenability