Which of the following statement is true about brittle fracture?
High temperature and low strain rates favour brittle fracture
Many metals with hexagonal close packed (H.C.P) crystal structure commonly show brittle fracture
Brittle fracture is always preceded by noise
Cup and cone formation is characteristic for brittle materials
Correct Answer :
B. Many metals with hexagonal close packed (H.C.P) crystal structure commonly show brittle fracture
Related Questions
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
Dye penetrant method is generally used to locate
Core defects
Surface defects
Superficial defects
Temporary defects
Ball bearings are, usually, made from
Low carbon steel
High carbon steel
Medium carbon steel
Chrome steel
The heat treatment process used for softening hardened steel is
Carburising
Normalising
Annealing
Tempering
Normalising of steel is done to
Refine the grain structure
Remove strains caused by cold working
Remove dislocations caused in the internal structure due to hot working
All of the above
Which of the following alloys does not have copper as one of the constituents?
Delta metal
Monel metal
Constantan
Nichrome
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
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
Which of the following represents the allotropic forms of iron?
Alpha iron, beta iron and gamma iron
Alpha iron and beta iron
Body centred cubic iron and face centred cubic iron
Alpha iron, gamma from and delta iron
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
Which of the following has highest specific strength of all structural materials?
Magnesium alloys
Titanium alloys
Chromium alloys
Magnetic steel alloys
Basic constituents of Monel metal are
Nickel, copper
Nickel, molybdenum
Zinc, tin, lead
Nickel, lead and tin
Cold rolled steel sheets contain carbon of the following order
0.1 %
0.2 %
0.4 %
0.6 %
Sulphur in pig iron tends to make it
Hard
Soft
Ductile
Tough
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
Argentite is the principal ore or raw material for
Aluminium
Tin
Zinc
Silver
The electric process of steel making is especially adapted to
Alloy and carbon tool steel
Magnet steel
High speed tool steel
All of these
Recrystallisation temperature is one
At which crystals first start forming from molten metal when it is cooled
At which new spherical crystals first begin to form from the old deformed one when a strained metal is heated
At which change of allotropic form takes place
At which crystals grow bigger in size
Which of the following metal shrinks most from molten state to solid state?
Cast iron
Cast steel
Brass
Admiralty metal
Gun metal contains
70% copper and 30% zinc
90% copper and 10% tin
85 - 92% copper and rest tin with little lead and nickel
70 - 78% copper and rest tin
Pipes for bicycle frames are made of
Cold rolled steel
Hot rolled steel
Forged steel
Cast steel
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
Which of the following alloys does not contain tin?
White metal
Solder admiralty
Fusible metal
Phosphor bronze
Iron-carbon alloys containing carbon ________ 4.3% are known as hypereutectic cast irons.
Equal to
Less than
More than
None of these
Connecting rod is usually made of
Aluminium
Low carbon steel
Medium carbon steel
High carbon steel
Railway rails are normally made of
Mild steel
Alloy steel
High carbon
Tungsten steel
Gamma-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
Cemented carbide tools are not found to be suitable for cutting
Brass
Cast iron
Aluminium
Steel
The hardness of steel primarily depends on
Percentage of carbon
Percentage of alloying elements
Heat treatment employed
Shape of carbides and their distribution in iron
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