Macrostructure of a material is, generally, examined by
Naked eye
Optical microscope
Metallurgical microscope
X-ray techniques
Correct Answer :
A. Naked eye
Related Questions
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
Nickel when added to copper improves
Machinability
Hardness
Hardness and strength
Strength and ductility
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
Wrought iron is
Hard
High in strength
Highly resistant to corrosion
Heat treated to change its properties
An example of amorphous material is
Zinc
Lead
Silver
Glass
The stiffness is the ability of a material to resist
Deformation under stress
Fracture due to high impact loads
Externally applied forces with breakdown or yielding
None of the above
Which of the following is an amorphous material?
Mica
Silver
Lead
Glass
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
Dislocations in materials refer to the following type of defect
Point defect
Line defect
Plane defect
Volumetric defect
Nodular cast iron is produced by adding ________ to the molten cast iron.
Nickel
Chromium
Copper
Magnesium
Beryllium bronze has
High yield point
High fatigue limit
Both (A) and (B)
None of these
Aluminium bronze contains
94% aluminium, 4% copper and 0.5% Mn, Mg, Si and Fe
92.5% aluminium, 4% copper, 2% nickel, and 1.5% Mg
10% aluminium and 90% copper
90% magnesium and 9% aluminium with some copper
The loss of strength in compression with simultaneous gain in strength in tension due to overloading is known as
Hysteresis
Creep
Visco elasticity
Boeschinger effect
Hardness of steel depends on
Amount of carbon it contains
The shape and distribution of the carbides in iron
Method of fabrication
Contents of alloying elements
Shock resisting steels should have
Low wear resistance
Low hardness
Low tensile strength
Toughness
Which of the following pipes is least corrosion resistant?
Brass
Mild steel
Cast iron
Wrought iron
Which of the following material has maximum ductility?
Mild steel
Copper
Nickel
Aluminium
Iron ore is, usually, found in the form of
Oxides
Carbonates
Sulphides
All of these
When steel containing less than 0.8% carbon is cooled slowly from temperatures above or within the critical range, it consists of
Mainly ferrite
Mainly pearlite
Ferrite and pearlite
Pearlite and cementite
Chromium when added to steel __________ the tensile strength.
Does not effect
Decreases
Increases
None of these
The percentage of carbon in low carbon steel is
0.05 %
0.15 %
0.3 %
0.5 %
Induction hardening is basically a
Carburising process
Surface hardening process
Core hardening process
None of these
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
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
Pig iron is the name given to
Raw material for blast furnace
Product of blast furnace made by reduction of iron ore
Iron containing huge quantities of carbon
Iron in molten form in the ladles
For the allotropic forms of iron, the points of arrest are
The points where no further change occurs
Constant for all metals
The points where there is no further flow of metal
The points of discontinuity
Mild steel belongs to the following category
Low carbon steel
Medium carbon steel
High carbon steel
Alloy steel
Which of the following metal shrinks most from molten state to solid state?
Cast iron
Cast steel
Brass
Admiralty metal
The temperature at which ferromagnetic alpha iron transforms to paramagnetic alpha iron is
770°C
910°C
1050°C
Below recrystallisation temperature
Which of the following metal is used for nuclear energy?
Uranium
Thorium
Niobium
All of these