Materials and Construction Flashcards
The behaviour of visco-elastic material is time dependent. This behaviour is common in __________ materials.
non-crystalline organic polymeric.
Coke oven regenerators are made of __________ bricks.
fire clay
Which of the following is universally employed as the low expansion metal in the bimetallic thermometer, which is an iron-nickel alloy containing 36% nickel and has very low co-efficient of expansion (l/20th of ordinary metals) ?
invar
Shock resisting steels should possess high
toughness
The purpose of nitriding the steel is to
harden its surface.
Ceramic recuperators are generally made of
silicon carbide.
Hammers and railway rails are normally made of
high carbon steel
Softness of silver can be converted into hardness by alloying it with small quantity of
copper & nickel
The addition of antimony in tin-based alloys improves its
deformation resistance.
The melleability of a material is the property by virtue of which it can be rolled or hammered into thin sheets. Which of the following materials has the miximum malleability ?
Lead
The main purpose of galvanising iron sheets is to
prevent the action of water.
The impure iron (pig iron) that is tapped out from blast furnace contains about __________ percent carbon.
4
Invar used in thermocouples is an alloy of nickel and
iron
Nickel (56%) and molybdenum (17%) alloys are called
hastealloy C
Lead pipes are not safe for carrying drinking water because water containing dissolved oxygen attacks lead thereby forming poisonous Pb (OH)2. Lead pipes are readily corroded by
acetic acid
Constituents of stellite are
cobalt, chromium and tungsten.
Residual magnetism in steel for magnets is increased by the addition of
cobalt
Presence of nickel in steel improves its
corrosion resistance.
Cementite is
all (a), (b) and (c).
Acetylene gas holder is made of
steel
Sulphur melting pit in the sulphuric acid plant is made of
steel or cement-brick lined.
The hardest material just prior to diamond in Mho’s scale is
corrundum
Percentage elongation of a material is a measure of its
ductility
Chlorination of benzene is done to produce benzene hexachloride (a pesticide) in a photochemical reactor lined with
lead or glass
Heavy duty bearings are usually made of
white metal
Dielectric strength of a material is
its capacity to withstand high voltage.
Which of the following stainless steels is non-magnetic ?
Austenitic
18-4-1 high speed steel contains 18%, 4% and 1% respectively of
tungsten, chromium and vanadium
Aluminium as a material of construction suffers from the disadvantage of
rather low tensile strength.
Babbit metal used for bearings is a____base alloy.
tin
18/8 steel is a/an __________ stainless steel.
austenitic
Cast iron has very high
compressive strength
Liquid ammonia is shipped in __________ containers.
glass
Cermets are __________ materials.
refractory
Cast irons are generally specified by their
tensile strength
Austenitic manganese steel used for making jaws of crushing machines contains about __________ percent manganese.
12-14
White cast iron is not
malleable
Galvanised iron is
protected from rusting
German silver used for decorative purposes contains maximum percentage of
copper
The metals occuring at the lower most position in the electromotive series
resist corrosion very strongly.
German silver in an alloy of
copper, nickel and zinc.
A suitable material of construction to use with fuming sulphuric acid is
monel
Which of the following crystal structures characterises the austenitic stainless steel?
Face centred cubic
Caustic soda is produced in a mercury cell having anode and cathode made respectively of moving mercury and
graphite and moving mercury.
Addition of __________ in steel can help in increasing the depth of hardness.
tungsten
Which of the following has the highest compressive strength ?
High carbon steel
Zinc is not used
as an alloying element in various bronzes.
Refined acetic acid storage vessel are made of
aluminium
Addition of __________ to the steel helps in increasing the residual magnetism in steel used for making magnets.
cobalt
Constantan is an alloy of
Cu (55%) & Ni (45%).
Babbit metals used for making bearings are
tin or lead based alloys.
Pipes for bi-cycle frames are made of __________ steel.
cold rolled
Which of the following materials may prove unsuitable for handling acetic acid (glacial & anhydrous) at 40°C ?
Brass, cast iron, mild steel and tin.
Interchain forces are the weakest in case of
both rubber & elastomers
__________ possesses viscoelastic properties.
Rubber
Steel tower used for the storage of oleum
need not be lined.
Plastics are
non-biodegradable.
Acetaldehyde is produced by hydration of acetylene in a sulphuric acid solution of mercuric sulphate. Hydration tower is made of
rubber lined mild steel
Wood is corroded by
all (a), (b) and (c)
Brass is an alloy of
copper and zinc
Lead
can not be work hardened.
Photographic plates are coated with
silver halide
Cast iron has
elastic limit close to ultimate breaking strength.
Locomotive boiler tubes are made of __________ alloys.
arsenic copper
Slow and progressive deformation of a material with time under constant stress is called
creep
Which of the following heat treatment processes is used for softening the hardened material ?
Tempering
Which of the following mechanical properties of a material is most structure insensitive ?
Modulus of elasticity (young’s modulus).
Mercury is transported in metal containers made of
iron
Which of the following would not be a suitable material of construction for handling aqueous hydrofluoric acid (HF) at 100°C ?
Stainless steel
Which of the following has the least carbon percentage ?
Wrought iron
The range of Mho’s scale of hardness is from
l to10
Which of the following pairs of elements may form an alloy ?
Iron & carbon
SO3 is absorbed using H2SO4 in a
packed steel tower lined with acid proof bricks.
Carbon percentage in medium carbon steel is around
0.35 to 0.5
The preferred material of construction for storage tanks for 98% sulphuric acid is
lead
The fermentor used for the production of ethyl alcohol from molasses is made of
copper bearing steel
Super conductors are those substances, which
offer no resistance to current flow.
Cermets are used for making
both (a) & (b)
The formation of oxide film on a metal due to atmospheric exposure reduces its
creep limit
A hardened steel essentially contains
martensite
Which one contains the least percentage of carbon ?
Wrought iron
Thermal shield used in high powered nuclear reactor to protect the walls of the reactor from radiation damage is made of
steel
All materials obey Hooke’s law within elastic limit. When elastic limit is reached, the tensile strain
increases very quickly.
Silico-manganese steels (containing 0.7% Mn, 0.5% C and 2% Si)
are used for leaf and coiled springs.
Which of the following is not a copper based alloy with nickel ?
Inconel
Which of the following alloys does not contain nickel ?
Babbit metal
An elastic behaviour of materials is expressed in terms of
relaxation time
Pure nickel is
ferromagnetic at room temperature.
In drop forging process, the forging is done by dropping the __________ at high velocity.
die with hammer
Which of the following is not an alloy of copper and tin ?
Monel metal
__________ is never shipped in glass carboys.
Ammonia
Lead is
used as a shock absorber (in mattress form) between the foundation and steel framework of skyscrapper buildings.
Nitriding of steel is done (in electric furnace) at __________ °C.
510
Addition of 2% nickel in steel makes it suitable for making
boiler plates, rivets etc.
The softest material just next to talc in the Mhos scale is
gypsum
Fatigue strength of a material increases by
under stressing the specimen
Specify the material of construction suitable for handling concentrated HNO3 at 100°C.
High silicon iron, Kel-F and teflon
Aluminium storage vessel can be used to store
none of these
Silicone rubber is not resistant to the corrosive action of
both (b) and (c)
Which metal is protected by the layer of its own oxide ?
Aluminium
Failure of a material is termed as fatigue failure, if it fails below the yield point. The resistance to fatigue failure of a material is measured by the
endurance limit
Bog iron used for the adsorption of H2S from coke oven gas is
an intimate mixture of saw dust and iron dust (i.e. moist ferric hydroxide).
Wrought iron is a suitable material of construction for handling __________ solutions.
alkalis & alkaline
Steel rods are used in reinforced concrete to increase its __________ strength.
tensile
Corrosion involves exchange of electrons in __________ corrosion.
both (a) & (b)
Straight silicon steel (containing Si from 0.5 to 5%) because of their low hysterisis loss and high magnetic permeability are used for electrical appliances. Which of the following electrical appliances made of silicon steel contains maximum percentage of silicon (about 4%) ?
High frequency transformers.
Which of the following has the least value of ultimate tensile strength (UTS) ?
Cast iron
__________ does not contain tin as an alloying material.
Brass
A metallic alloy in general as compared to their pure metal components is
more corrosion resistant.
Pick out the wrong statement.
Wrought iron can not be easily forged and welded.
The increase in hardness of metal due to its cold working is termed as the __________ hardening.
work
Copper is dissolved from its ore by H2SO4 in a percolation tank made of
reinforced concrete lined with lead
Bearings subjected to light load are made of
phosphorous bronze
Softening of hardned steel is done by its
tempering
Maximum permissible sulphur content in steel is __________ percent.
0.055
Ceramic materials fabrication can not be done by
welding
Which has the maximum melting point out of the following ?
Wrought iron
Cast iron is
all (a), (b) & (c)
Which of the following has no effect on the carbide forming tendency in steels ?
Phosphorus
Approximate value of the modulus of elasticity for steel is about __________ x l06kg/cm2.
2
Carbon is present in steel wholly in the
combined form.
Carbon supply in pack carburising process is in the form of
charcoal
In SO3 absorber (Contact Process), packing material used is of
chemical stoneware
Presence of manganese in alloy steel improves its
abrasion resistance & toughness.
Sulphuric acid is mixed with ground phosphate rock (to produce phosphoric acid) in a steel digestor lined with
lead or acid-proof bricks
A material is called ‘ductile’, if it can be
drawn into wires.
A chemical change takes place when iron
rusts
Evaporator used for concentrating tomato juice is made of
stainless steel-glass lined
High carbon steel contains more than __________ percent carbon.
0.5
The main constituent of carborundum is __________ carbide.
silicon
For storing water and acid free benzol, use a __________ vessel.
steel
The chlorinator used in the manufacture of DDT is made of
glass lined steel
Reduction in the grain size reduces the __________ of the material.
creep resistance
Age hardening is concerned with
duralumin
Which of the following undergoes granular fracture ?
Steel
Ball bearings are normally made of __________ steel.
chrome
The electrical conductivity of a __________ decreases with rise in temperature.
metal/alloy
Which one occupies the lowermost position in the electromotive series of metals ?
Noble metals (Ag, Pt, Au)
Addition of nickel to copper improves its
hardness
Presence of even 0.005% of __________ in copper makes it highly brittle, rendering it useless for wire-drawing.
bismuth
High speed cutting tool steels contain about __________ percent of tungsten.
18-20
The ‘bomb’ in the bomb calorimeter is made of
molybdenum stainless steel
Which of the following is produced by condensation polymerisation ?
Bakelite
The crystal structure of most of the common metals is
cubic
Telfon (PTFE) is corroded by
none of these
Hastelloy C is a good material of construction in chemical process industry, since it is
light and resists attack by acids.
Mixing vessel used for the chlorination of methane to produce methyl chloride is made of
cast iron
The loss of strength in compression which occurs, when there is a gain of strength in tension due to over loading is called
Bauschinger effect.
Pick out the wrong statement.
Thermal conductivity of aluminium is higher than that of copper; hence it is increasingly used for utensil making.
The specific gravity of coal depends mainly on its __________ content.
ash
Carbon percentage is the same in cast iron and
pig iron
Pick out the wrong statement.
The ability of a material to fracture without appreciable deformation is called its ductility.
Which of the following has the highest density and the lowest melting point ?
Lead
In order to be called steel, an alloy should have iron percentage greater than
80
Nickel is a constituent of
monel metal
Soap kettle used in the production of laundry soap is made of
steel with top section nickel clad or stainless steel
Nickel made/clad equipments are suitable for handling
fruit juices, milk & its products and caustic soda solution.
Tubes of multiple effect evaporator used for concentration of sugar cane juice are made of
copper
In hot wire aneomometer used for gas flow measurement, the wire is normally made of
platinum
The heat treatment process to which castings and the steel balls produced by cold heading are subjected is
normalising
Mild steel is used for making
channels
Presence of 0.3 to 0.5% arsenic in copper increases its
tenacity & hardness
The heat treatment process applied to cold formed steel parts is
solution annealing
The largest consumption of zinc for alloys is in the making of
brasses
Plate and frame filter press is usually made of
cast iron
Ammonium chloride solution is stored/ treated in __________ vessels/pipes.
rubber or durmet-20 lined
Nickel and copper are the basic constituents of
monel metal
Copper has very low
tensile strength
Hardest material so far found is
Hardest material so far found is
Most suitable material of construction for the storage of concentrated nitric acid is
aluminium or chromium alloys (Cr > 18% for cold acid)
The most resistant material to alkaline corrosion is
nickel
Tin coating is not done by
vaporising
Stainless steel is not corroded by
nitric acid (10%).
__________ is added in stainless steel to prevent inter crystal corrosion.
Niobium
Nickel is a __________ material.
ferromagnetic
Babbit metal is not a
pure metal
Which of the following alloys does not contain nickel ?
Babbit metal
Which of the following is the lightest of engineering metals ?
Magnesium
Evaporators used in caustic soda recovery and production plant are made of
monel metal
With increase in carbide/graphite ratio in cast iron, its
both (a) and (b).
The fermentor used in the production of pencillin (by deep fermentation process) is made of
glass lined steel
Nickel (76%) and chromium (15%) alloys are termed as
inconel
Low carbon steels are those in which carbon percentage is around
0.1 to 0.35
White metal is an alloy of
none of these
The carbonating tower used in Solvay process of soda ash manufacture is made of
cast iron
For platinum thermocouples, lead wires are made of
copper & copper-nickel alloys.
High resistance electrical heating elements/wire are not made of
marageing steel
Cast irons are generally specified by their
tensile strength
Which one is remelted and poured into moulds to get cast iron ?
Pig iron
Wood metal is not used for making
storage tank for storing brine and caustic soda.
An ideal material of construction for the storage of 50% caustic soda solution would be
monel
Which of the following is the hardest ?
Austenite
Which of the following alloy steels is the most suitable for making gun barrels and projectiles ?
Nickel-chrome steelZircalloy used as a fuel cladding material in a nuclear reactor (thermal) is an alloy of zirconium
The process of heating the cold pressed metallic powder is called __________ in powder metallurgy.
sintering
Sulphuric acid pickling tanks are lined with
rubber
Valves in pipe size of 2” and under are normally made of
brass
Ceramic materials are
stronger in compression than in tension
Which is an amorphous material ?
Glass
In the Contact process of sulphuric acid manufacture, 98% acid cooler is made of
cast iron
Platinum and silver are corroded by
none of these
Zircalloy used as a fuel cladding material in a nuclear reactor (thermal) is an alloy of zirconium
tin, nickel, iron and chromium
Dead mild steel, which contains 0.10 to 0.15 percent carbon is used for making
flanges
Work hardening of a material
decreases its ductility.
The material used in the filament of electric bulbs is
tungsten
Caustic soda can be stored in __________ drums.
steel
Wrought iron is
malleable & ductile; and hence is used for chain links, hooks & couplings.
Perspex is nothing but
acrylic sheet
Centrifugal pump made of pyrex or glass can’t be used to pump
alkaline solutions.
Ability of a material to __________ is indicated by its damping capacity.
absorb vibration
Corrosion resistance of steel is increased by the addition of
nickel and chromium.
Hydrochloric acid is __________ corrosive to common metals.
highly
Tank furnace used for melting of glass is made of
refractory blocks
Spray dryer for evaporating milk to produce milk powder is made of
stainless steel
Chromel (Nichrome) is an alloy of
nickel and chromium.
Which of the following is not an alloy of nickel and chromium ?
Duralumin
Thermoplastic resins are those polymers, which
easily deform under pressure at high temperature.
The temperature at which new grains are formed in the metal is called the __________ temperature.
recrystallisation
Molten phthalic anhydride is stored in a/an __________ vessel.
aluminium
Fatigue failure of a material results from __________ stress.
fluctuating
Fermenter used in the production of pen-cillin by deep fermentation proces is a __________ lined steel vessel
glass
Pick out the wrong statement.
Tungsten has a body centred cubic (bcc) crystal lattice structure.
Ability of a material to absorb energy in deformation in the plastic range is characterised as its
toughness
Monel alloy is
used for making steam valves and turbine blades as it resists steam attack at high temperature.
Molybdenum steels containing 0.15 to 0.40% molybdenum
are used for automobile parts like gears, axle, shaft, bearings etc.
Kel-F is a material, which is
all (a), (b) and (c).
Presence of high amount of silicon in cast iron
increases the formation of graphite.
Rubber lined pumps can be used to pump
all (a), (b) and (c)
Titanium metal
is used in oceanographic and space exploration applications.
Purity of electrical grade aluminium should be ≥ __________ percent.
99.5
Maximum consumption of zinc is in
galvanising
Hardest materials so far found is
diamond
Galvanising is not a zinc diffusion process. A zinc diffusion process is termed as
sheradising
Which of the following commercial metals is most abundantly found in India ?
Aluminium
Tin vessels are corroded by
none of these
Out of the following, copper vessels are the most suitable for the storage of
dry chlorine & dry fluorine.
Tempering of steel is done to make it
soft
Concrete tank can be used to store
saturated brine
Zinc is highly __________ at room temperature.
resistant to atmospheric corrosion
Which of the following constituents of cast iron is mainly responsible for imparting it an anti-corrosive property ?
Silicon
Most common stainless steel type 316, which is highly resistant to corrosion contains
16-13% Cr 10-14% Ni and 2-3% Mo.
Sheardising process is used for
surface coating.
The maximum percentage of chromium that can be added to steel is about
18
Which of the following is a non-magnetic material ?
Zinc
An alloy used as thermocouple material comprises of 40% nickel and 60% copper. It is called
constantan
The material of construction of pressure mills used for squeezing out the juice from sugar cane is
cast iron
Rotary driers are generally made of
mild steel
Presence of high phosphorous in cast iron increases its
fluidity
The phenomenon in which slow extension of material takes place with the time at constant load is called
creep
A material capable of undergoing large permanent deformation, when subjected to compression is termed as
malleable
__________ is used for examining the macro-structure of a material.
Visual inspection by naked eye
High speed steel tools retain their hardness upto a temperature of __________ °C.
900
Dry chlorine can be handled in a vessel made of
iron or steel
Brine solution is stored/treated in __________ lined vessels/pipes.
nickel
Steel balls for ball bearings are generally made of __________ steel.
carbon chrome
Beehive coke ovens are made of __________ bricks.
silica
Muntz metal is a/an alloys of
copper & zinc
Rotary kilns in cement industry are lined with____bricks.
high alumina & high magnesia
Steel will respond to hardening by heat treatment processes, only when the minimum carbon content in it is __________ percent.
0.2
Which of the following will have the highest melting point ?
Wrought iron
Galvanising is generally done on
low carbon steel
Carbon is present in the combined form (carbide) in case of
all (a), (b) & (c)
Chilled iron castings are
highly wear resistant
A hardness depth of about 3 mm can be achieved by induction hardness in __________ seconds.
5
Presence of nitrogen in steel
makes it brittle.
Very high sulphur in pig iron makes
its casting unsound.
Amount of energy that a material can absorb before its fracture is a measure of its
toughness
Anodic material used for the cathodic protection of underground buried steel pipeline is
zinc or magnesium
Bush bearings are made of
phosphorous bronze
Alinco, which is a aluminium-cobalt-nickel steel, is used for making
powerful magnets
Slow plastic deformation of metals under a constant stress is termed as __________ failure.
creep
Corrosion resisting properties of cast iron are significantly improved by the addition of 12 - 15% of
silicon
Pick out the wrong statement
both (b) and (c)
Duriron is
all (a), (b) and (c).
Pick out the correct statement.
Hardening of a soft metal can be done by alloying it with another metal or non-metal.
Cast iron detachable joint is used in __________ pipes.
steel
Tin coating on metals is not done by
powder metallurgy
The softest material just next to talc in the Mho’s scale is
gypsum
18/8 stainless steel means, that it contains
18% chromium and 8% nickel.
Glass is corroded by
fluorine (dry or wet)
Iron alloyed with carbon upto 2% is called
none of these
Which of the following is a low melting point metal ?
tin
Trough of an apron conveyor is made of
either (b) or (c)
Pick out the wrong statement.
Cold working of a metal decreases its fatigue strength.
Which of the following finds the least commercial use ?
Pure iron
Which of the following is the most widely used insulating material for steam carray-ing pipelines ?
Glass wool and 85% magnesia
Silicon percentage in iron castings to have maximum hardness should be about
0.8
Nickel as a material of construction
is used as an alloying element for both ferrous & non-ferrous alloys.
__________ moulding process can not be used for thermoplastic plastics.
Injection
Which of the following crystal structures characterises the ferritic stainless steel ?
Body centred cubic
‘Semi steel’ is
both (a) and (b).
Gun metal is an alloy of
copper, tin and zinc
Carbon content in steel is __________ percent.
0.1-2
Nitriding of steel is a process for
case hardening
Which of the following has a very high carbide forming tendency in steels ?
Vanadium
The most distinguished property of malleable cast iron is its high
ductility
Non-ferrous metals and hard steels do not exhibit a definite yield point, when pulled in the testing machine and hence for these cases, a better measure of their elastic properties is defined by the __________ stress.
proof
Which of the following is the hardest material ?
Corrundum
Which of the following material of construction may be recommended by a chemical engineer for handling a gaseous chlorine (dry or wet) stream in a fluid flow system ?
High silicon iron, silicon rubber, Kel-F and teflon.
Biological shield in a nuclear power reactor is made of
concrete
Caustic soda is transported in __________ lined containers.
either (b) or (c)
Acid proof stoneware
all (a), (b) and (c).
Diamagnetic materials are magnetised
in a direction opposite to that of the applied field.
High degree of toughness is a must for
shock resisting steel
‘Hypersil’ is a __________ steel.
silicon
__________ can replace tungsten in high speed steel,
Molybdenum
Polythene (low or high density) containers are not corroded by
sulphuric acid (10%) at room temperature.
Bronze is an alloy of copper and
tin
Which of the following exercises most powerful influence on the mechanical properties of steel ?
Carbon
Percentage of silver in German silver is
0
Balls in a ball mill are usually made of
steel
DDT is shipped in
either (b) or (c)
Constantan used in thermocouples is an alloy of
none of these
A material is able to retain the deformation permanently by virtue of its
plasticity
__________ steel is widely used for the manufacture of motor car crankshafts.
Chrome
Galvanising (i.e., zinc coating) of steel sheets is done to
both(a) & (b).
Which of the following is not a nickel based alloy ?
Babbit metal
Coke oven walls are lined with __________ bricks.
silica
Iron rust is
hydrated ferric oxide.
Urea autoclave is made of
stainless steel
Mild steel is
a low carbon steel (0.05 to 0.3% carbon).
Dilute sulphuric acid is transported in __________ pipes.
lead
__________ alloys have the highest specific strength of all the structural materials out of the following.
Titanium
100% H2SO4 at 30°C can’t be stored in a vessel made/lined with
aluminium, tin and rubber.
Carbon content in plain carbon steel is __________ percent.
0.35 to 0.45
Duralumin is an alloy of
aluminium, copper and manganese.
Silicon percentage in acid resistant cast iron is about
14
Concentrated HCl at 30°C can be stored in a vessel made of
PTFE and porcelain.
Which of the following stainless steels is non-magnetic ?
Austenitic
A magnetic material becomes __________ above the Curie temperature.
paramagnetic
Which of the following is not a non-ferrous alloy ?
Meehanite
Which of the following is the most elastic material ?
Steel
Water gas generator is made of
carbon steel-brick lined
The digester of a Gobar gas plant is a
masonry well
The ability of a material to offer resistance to scratching or indentation is a measure of its
hardness
Brine (15% concentration) can be stored in a vessel made of
monel
Generally __________ are subjected to galvanising (i.e., zinc coating).
low carbon steels
A material no longer behaves elastically beyond
elastic limit
When the steel is subjected to normalising, its __________ decreases.
ductility
The most commonly used resin for making reinforced plastic is
unsaturated polyester
Most suitable material for high pressure vessel operating at 500 atm. and 500° C is
molybdenum stainless steel.
Brinell Hardness Number (BHN) for talc is approximately in the range of
20-30
Dies for wire drawing are generally made of
carbides
Dip stick used for measuring the level of petro fuels (e.g. petrol, diesel, fuel oil etc.) in the storage tank is usually made of
brass
Which of the following contains maximum percentage of carbon ?
Saws for cutting steel
Tempering of steel is done to make it
soft
Aluminium alloy is one of the most suitable materials of construction for aircrafts mainly due to its
high strength to weight ratio.
Babbit metal used for making bearings should have
high-co-efficient of friction between journal and bearing.
Vessels made of __________ can be used to store dry chlorine.
steel or iron
For spinning viscose rayon, the extrusion spinnerettes are made of
platinum or gold alloys
Alpha iron is stable __________ °C.
upto 910
Babbit metal (used for making bearings) comprises of
mainly tin (85%) and lead.
Hydrochloric acid is stored in a __________ steel vessel.
rubber lined
Chrome vanadium steels usually contain 0.8 to 1.1% Cr, 0.25 to 0.35% C and < 0.25% V. It is
used for making axle & shafts of aeroplanes, automobiles and locomotives.
Which of the following alloying elements is present in maximum percentage in high speed steel.
Tungsten
Electronic structure of a material is generally studied by
spectroscopic techniques
Which of the following has the poorest wel-dability ?
High-carbon steel
Creep is not exhibited at low temperature by
lead
Nickel and molybdenum are the basic constituents of
hastealloy
Spark plugs, ignition tubes and electrodes are made of nickel __________ alloys.
manganese
A steel alloy containing 36% nickel is called __________ , which has a zero co-efficient of expansion.
invar
Which of the following is not used as the ceramic material in ‘cermets’ ?
Nitrides
Glass lined vessels are not used for handling/storing
hydroflouric acid
For handling sulphuric acid of 95% strength, the suitable material of construction for pipes is
cast iron
Cast iron has
its elastic limit very close to ultimate breaking strength.
Which of the following is not an alloy of tin?
German silver
Which of the following is the easiest to bend?
Wrought iron
Common house hold glass (i.e., soda-lime glass) is a/an __________ material.
partly crystalline
In the kraft (sulphate) process for the paper manufacture, the digestor is made of
stainless steel
Cast iron and steel pipes are produced by __________ casting.
true centrifugal
Cold worked steel parts are normally subjected to
annealing
Graphite is a good
both (b) & (c).
Lead alone is not used in storing equipment, because it
is having low creep strength.
H2SO4 (< 50% concentration) is corrosive to
aluminium, mild steel, stainless steel, concrete & tin.
In the Kraft process of sulphate paper pulp manufacture, the black liquor and the white liquor storage tank is made of
steel
A bearing metal should not have
low thermal conductivity.
__________ is not a case hardening process.
Annealing
Materials having __________ lattice structure are usually most ductile.
f.c.c.
Invar contains the highest percentage of
iron
Metalloid is
an element which exhibits the properties of both metal & non-metal.
The ability of a material to absorb energy in the elastic range is a measure of its
resilience
Phenol is not shipped in
cast iron containers.
To improve the machinability of steel, it is generally subjected to
spheroidising
Glass lined vessels are not used for handling
hydroflouric acid
Hardening of steel is not possible unless it is heated __________ critical point.
above the lowest
Hydrochloric acid absorber in made of
karbate
Pick out the wrong statement.
Tin can be readily and very easily drawn into very fine wire.
Thermometer bulb & capillary in case of mercury filled pressure spring expansion thermometer is normally made of __________ as mercury does not amalgamate with it.
stainless steel
Presence of silicon in steel
decreases the blow holes formation tendency in castings.
Pick the odd man out of the following.
Calorising
Cold work tool steel should have
high wear resistance
Aqueous nitric acid is stored in
stainless steel vessel
Addition of tungsten to steel imparts
cutting hardness
Hot working of lead is carried out at
room temperature
Which of the following is a light alloy ?
Dow metal
Thermosetting resins are those polymers, which
do not increase in plasticity with rise in temperature.
Ceramic materials
all (a), (b) and (c).
Light weight metallic alloy used in aircraft industry is
duralumin
Which of the following is an alloy of nickel and copper ?
Monel
Gunmetal and bronze are not corroded by the action of
synthetic detergent solution.
Atmospheric corrosion of metals result from their
slow oxidation
Karbate is
both (b) and (c).
To improve the machinability of steel by its softening, it is subjected to
annealing
Which one has the maximum tensile strength out of the following ?
Nodular cast iron
Material of construction of pipe generally used for conveying water in India is
cast iron
Which of the following is the softest material ?
Calcite
Thermosetting polymers are
cast molded
Maximum consumption of lead is in the manufacture of
storage batteries.
Clock pendulums are usually made of __________ steel.
none of these
Which of the following is produced by addition polymerisation ?
Polybutadiene
With increase in the carbon percentage in the steel, its
all (a), (b) and (c).
__________ is used for determining the tensile strength of steels.
Universal testing machine
Mild steel storage vessels are suitable for the storage of
anhydrous ammonia
Mild steel is a/an __________ steel.
low carbon
Hardened steel is softened by
tempering
Which of the following is not shipped in mild steel containers ?
Formic acid
Addition of lead, sulphur and phosphorus to low carbon steel helps in improving its
machinability
Maximum consumption of copper is in
electrical industry.
Maximum carbon content in cast iron is __________ percent.
4.3
Manganese in steel affects its
tensile strength
Lead lined equipments & vessels are suitable for handling
sulphuric acid upto 60°C.
Carbon tetrachloride can be stored in a storage vessel made of
all (a), (b) and (c)
The process of coating steel sheets by zinc to improve its corrosion resistance is called
galvanising
__________ does not contain copper as an alloying element,
Nichrome
Reactor used in the production of polyvinyl chloride (PVC) is made of
nickel or glass lined steel
__________ is added in low carbon steel to raise its yield point.
Manganese
__________ iron is produced, when molten pig iron is allowed to cool gradually.
Grey cast
Cast iron vessels are not suitable for the storage of
wet SO2
Condenser tubes are not made of
wood metal
Tin in its pure form is used for making
all (a), (b) and (c).
Addition of __________ in steel is helpful in increasing the depth of hardness.
chromium
Hydrochloric acid is stored in a__vessel.
rubber lined steel
Brass tubes are used in the manufacture of tubes of evaporators used in sugar and salt industries, mainly because of its
high corrosion resistance.
Pick out the wrong statement.
Presence of silicon in steel decreases its electrical resistance.
Ferric stainless steels compared to austenitic stainless steels
all (a), (b) and (c).
Liners of a ball mill are never made of
lead
Most of the common metals have __________ crystal structure.
cubic
Cast iron is a __________ material.
brittle
Hydrocyanic acid is not shipped in
cast iron vessels.
Spark plugs are made of
high alumina ceramic
The high expansion metal normally used in the bimetallic thermometer is __________ temperature measurement.
both’a’ & ‘b’
Neutraliser tank used for reacting nitric acid with ammonia for the production of ammonium nitrate is made of
stainles steel
Gas holder of a gobar (cowdung) gas plant is made of
mild steel
A material capable of undergoing large permanent deformation, when subjected to tension is termed as
ductile
Bell metal is an alloy of
copper & tin
Mercury is transported in metal containers made of
iron
Lead pipe is
all (a), (b) and (c).
Inconel is an alloy of
iron, nickel and chromium
A measure of toughness of a material is its
yield strength
Polymerisation reactor used for the production of styrene butadiene rubber (SBR) is made of
stainless steel or glass lined vessel
Cast iron is having very high
proximity between its elastic limit and ultimate breaking strength.
The material of construction of bearings is
babbit metal
Wrought iron is a suitable material of construction for handling __________ solutions.
alkalis & alkaline
Hastelloy comprises of
molybdenum and nickel
Metalloid is
an element, which exhibits the properties of both metal & non metal.
Stainless steel contains
chromium and nickel
Tin base and lead base alloys are used for bearing materials. Tin compared to lead has lower
abundant availability.
Metal at the top of the electromotive series is
most active
Fatigue failure of a material may occur, when it is subjected to __________ stress.
fluctuating
Presence of even very minute amount (say 0.1%) of __________ in copper, reduces its electrical conductivity very seriously.
both (b) and (c)
High speed steel should have high
both(b) & (c)
Lead pipes are not safe for carraying drinking water, because water, containing dissolved oxygen attacks lead thereby forming poisonous Pb(OH)2. Lead pipes are readily corroded by
acetic acid
An alloy of iron containing 4% carbon is called
none of these
Steel pipes are normally manufactured by __________ process.
extrusion
Polymorphism is not exhibited by
none of these
Rubber lined vessels are corroded by the action of
all (a), (b) and (c)
__________ of a material results, when its strength is increased & ductility is decreased by heating at a relatively lower temperature after cold working.
Strain ageing
Which of the following metals in not used for coating of the base metal to guard it against corrosion ?
Magnesium
Brass container is suitable for storing
beer
Aqueous nitric acid is stored in __________ vessel.
cast iron
A metallic alloy in which one of the constituent metal is __________ , is called an amalgam.
mercury
Graphite is corroded by
none of these
Carbon is present in the uncombined (graphitic) form in case of
cast iron
Among the tin containing alloys, __________ consumes the maximum amount of tin.
solder
The hardest material just prior to diamond in Mhos scale is
corrundum
The damage/deterioration of metals by the __________ action of fluids is called ‘erosion’.
abrasive
Cast iron compared to steel is better in
fluidity & castability
Plasticisers are added to polymers to improve their
softness & flexibility.
Polymerisation reactor used in the production of styrene butadiene rubber (SBR) is made of
stainless steel or glass lined steel
Sulphuric acid is mixed with ground phosphate rock (to produce phosphoric acid) in a steel digestor lined with
acidic refractory
The softest material in Mho’s scale (for measuring hardness) is
talc
Acetaldehyde is shipped in __________ drums.
either (b) & (c)
Monel metal is an alloy of
nickel and copper.
German silver is an alloy of copper, nickel and
zinc
The presence of impurities in iron
decreases its melting point.
Which of the following alloy steels has the energy saving properties making it suitable for use in electrical machines ?
Silicon steel
Visco-elastic behaviour of materials which is time dependent is common in
non-crystalline organic polymer
Which of the following is not an alloy of copper ?
Pewter metal
Which of the following is the most prone to atmospheric corrosion ?
Iron
As the impurities are oxidised, the melting point of iron
increases
In a plate type heat exchanger, heat transfer plates are never made of
cast iron
Compressive strength of wood is usually more along the grains. The tenile strength of wood as compared to that of steel is about
one fifth
Ball bearings are generally made of
chrome carbon steel
Mild steel is a/an __________ steel.
low carbon
Maximum carbon content in any variety of steel can be upto 1.3%. Steel containing 0.4% Carbon is not used for making
chiesels
Which is the purest form of iron ?
Wrought iron
White cast iron as compared to grey cast iron is
all (a), (b) & (c)
Combination of metals and ceramics are called
cermets
__________ iron is produced, when molten pig iron is chilled suddenly.
White cast
Which of the following is the most suitable material of construction for evaporator & its tubes for concentrating NaOH solution to 70%?
Nickel
Vycor, a widely used material for making ‘thermal wells’ in temperature measurement, is a
glass
‘Age hardening’ of duralumin is due to
both (a) & (b)
__________ is a donor impurity for semi-conductors.
Antimony
Post weld heat treatment is done by
stress relieving
How many atoms are there per unit cell in a body centred cubic lattice system ?
2
Presence of cobalt in steel improves its
cutting ability
In cold working of metal as compared to its hot working
appreciable strain hardening is produced.
Nickel base alloys with __________ are known as monel metal.
copper
Wrought iron is having very high
corrosion resistance.
When iron is rusted, it is
oxidised
Containers made of high silicon cast iron (14% Si) are not suitable for the storage of
hydrochloric acid (concentrated).
How many molecules per unit cell are there in a face centred cubic lettice ?
4
Which of the following comprises of hydrocarbons ?
Rubber