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
Correct Answer :
D. Boeschinger effect
Related Questions
Which of the following alloys does not have copper as one of the constituents?
Delta metal
Monel metal
Constantan
Nichrome
Which of the following pipes is least corrosion resistant?
Brass
Mild steel
Cast iron
Wrought iron
Which of the following element results in presence of free graphite in C.I.?
Carbon
Sulphur
Silicon
Manganese
The material widely used for making pendulums of clocks is
Stainless steel
High speed steel
Heat resisting steel
Nickel steel
Combined carbon in iron makes the metal
Soft and gives 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
Aluminium bronze contains aluminium and copper in the ratio of
50 : 50
40 : 60
60 : 40
10 : 90
Induction hardening is basically a
Carburising process
Surface hardening process
Core hardening process
None of these
Hardness of martensite is about
RC 65
RC 48
RC 57
RC 80
The portion of the blast furnace below its widest cross-section is called
Hearth
Stack
Bosh
Throat
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
The defect which takes place due to imperfect packing of atoms during crystallisation is known as
Line defect
Surface defect
Point defect
None of these
A material is said to be allotropic, if it has
Fixed structure at all temperatures
Atoms distributed in random pattern
Different crystal structures at different temperatures
Any one of the above
Super conduction by metals is observed in the temperature range of
Below 10°K
Above 100°K
Around 0°C
Around 100°C
The electric process of steel making is especially adapted to
Alloy and carbon tool steel
Magnet steel
High speed tool steel
All of these
Nickel in steel
Improves wear resistance, cutting ability and toughness
Refines grain size and produces less tendency to carburisation, improves corrosion and heat resistant properties
Improves cutting ability and reduces hardenability
Gives ductility, toughness, tensile strength and anticorrosion properties
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 presence of hydrogen in steel causes
Reduced neutron absorption cross-section
Improved Weldability
Embrittlement
Corrosion resistance
The correct composition of Babbitt metal is
87.75% Sn, 4% Cu, 8% Sb, 0.25% Bi
90% Sn, 2% Cu, 4% Sb, 2% Bi, 2% Mg
87% Sn, 4% Cu, 8% Sb, 1% Al
82% Sn, 4% Cu, 8% Sb, 3% Al, 3% Mg
Eutectoid reaction occurs at
600°C
723°C
1147°C
1493°C
Which of the following iron exist between 910°C and 1403°C?
α-iron
β-iron
γ-iron
δ-iron
Which of the following property is desirable for materials used in tools and machines?
Elasticity
Plasticity
Ductility
Malleability
An alloy of copper, tin and zinc is known as
Brass
Bronze
Gun metal
Muntz metal
In grey cast iron, carbon is present in the form of
Cementite
Free carbon
Flakes
Spheroids
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
When medium carbon steel is heated to coarsening 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
The strength is the ability of a material to resist
Deformation under stress
Externally applied forces with breakdown or yielding
Fracture due to high impact loads
None of these
Monel metal is an alloy of
Nickel and copper
Nickel and chromium
Nickel, Chromium and iron
Copper and chromium
When filing or machining cast iron makes our hands black, then it shows that ________ is present in cast iron.
Cementite
Free graphite
Both A and B
None of these
Admiralty brass used for steam condenser tubes contains copper and zinc in the following ratio
50 : 50
30 : 70
70 : 30
40 : 60
High carbon steel carries carbon percentage
0.1 to 0.3 %
0.3 to 0.6 %
0.6 to 0.8 %
0.8 to 1.5 %