(4) Materials and Construction Flashcards
The behaviour of visco-elastic material is time dependent. This behaviour is common in __________ materials.
-non-crystalline solid
-crystalline
-rubberry
-non-crystalline organic polymeric.
non-crystalline organic polymeric.
Coke oven regenerators are made of __________ bricks.
-fire clay
-silica
-low thermal conductivity
-high electrical conductivity
-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
-Constantan
-Chromel
-Alume
Invar
Shock resisting steels should possess high
-hardness
-toughness
-tensile strength
-wear resistance
toughness
The purpose of nitriding the steel is to
-harden its surface.
-soften its surface.
-improve its reliability.
-none of these.
-harden its surface.
Ceramic recuperators are generally made of
-silicon carbide.
-calcium carbide.
-fireclay bricks.
-high alumina bricks.
-silicon carbide.
Hammers and railway rails are normally made of
-mild steel
-dead mild steel
-medium carbon steel
-high carbon steel
-high carbon steel
Softness of silver can be converted into hardness by alloying it with small quantity of
-copper & nickel
-zinc
-aluminium
-tin
-copper & nickel
The addition of antimony in tin-based alloys improves its
-rupture strength and hot hardness.
-impact strength and bonding strength.
-deformation resistance.
-wear resistance
-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
-Copper
-Aluminium
-Wrought iron
Lead
The main purpose of galvanising iron sheets is to
-harden the surface.
-increase its glossiness and lustre.
-prevent the action of water.
-prevent the action of oxygen.
-prevent the action of water.
The impure iron (pig iron) that is tapped out from blast furnace contains about __________ percent carbon.
0.2
2
4
8
4
Invar used in thermocouples is an alloy of nickel and
-iron
-copper
-chromium
-lead
iron
Nickel (56%) and molybdenum (17%) alloys are called
-monel
-hastealloy C
-inconel
-bronzes
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
-dilute HCI
-acetic acid
-concentrated H2SO4
-none of these
-acetic acid
Constituents of stellite are
-zinc, copper and nickel.
-cobalt, chromium and tungsten.
-zinc, aluminium and nickel.
-nickel, cobalt and vanadium.
-cobalt, chromium and tungsten.
Residual magnetism in steel for magnets is increased by the addition of
-nickel
-cobalt
-tungsten
-chromium
cobalt
Presence of nickel in steel improves its
-corrosion resistance.
-cutting ability.
-wear resistance.
a-ll (a), (b) and (c).
corrosion
Cementite is
-Fe3C chemically.
-a compound of carbon and iron.
-characterised by an orthorhombic crystal structure.
-all (a), (b) and (c).
-all (a), (b) and (c).
Acetylene gas holder is made of
-copper
-cast iron
-steel
-monel metal
-steel
Sulphur melting pit in the sulphuric acid plant is made of
-lead lined stainless steel.
-cast iron.
-steel or cement-brick lined.
-hard wood.
-steel or cement-brick lined.
The hardest material just prior to diamond in Mho’s scale is
-topax
-carborundum
-corrundum
-calcite
corrundum
Percentage elongation of a material is a measure of its
-ductility
-brittleness
-toughness
-malleability
-ductility
Chlorination of benzene is done to produce benzene hexachloride (a pesticide) in a photochemical reactor lined with
-karbate
-lead or glass
-fireclay bricks
-PVC
-lead or glass
Heavy duty bearings are usually made of
-white metal
-phosphorous bronze
-monel
-zinc
-white metal
Dielectric strength of a material is
-its energy stroage capacity.
-a magnetic property.
-its capacity to resist the flow of current.
-its capacity to withstand high voltage.
-its capacity to withstand high voltage.
Which of the following stainless steels is non-magnetic ?
-Ferritic
-Martensitic
-Austenitic
-None of these
Austenitic
18-4-1 high speed steel contains 18%, 4% and 1% respectively of
-tungsten, vanadium and chromium
-tungsten, chromium and vanadium
-vanadium, chromium and tungsten
-chromium, tungsten and vanadium
-tungsten, chromium and vanadium
Aluminium as a material of construction suffers from the disadvantage of
-very high cost.
-rather low tensile strength.
-very low strength to weight ratio.
-scarce availability.
-rather low tensile strength.
Babbit metal used for bearings is a____base alloy.
-tin
-lead
-aluminium
-copper
-tin
18/8 steel is a/an __________ stainless steel.
-austenitic
-ferritic
-martensitic
-none of these
-austenitic
Cast iron has very high
-compressive strength
-ductility
-shock resistance
-resistance to brittleness
-compressive strength
Liquid ammonia is shipped in __________ containers.
-steel
-aluminium
-glass
-lead lined
glass
Cermets are __________ materials.
-refractory
-reinforced
-abrasive
-fully metallic
refractory
Cast irons are generally specified by their
-carbon content
-tensile strength
-hardness
-manufacturing process
-tensile strength
Austenitic manganese steel used for making jaws of crushing machines contains about __________ percent manganese.
1.5-2
3.5-4.5
7-9
12-14
12-14
White cast iron is not
-malleable
-whitish in color
-brittle
-strong and hard
malleable
Galvanised iron is
-harder
-protected from rusting
-alumina coated iron
-none of these
-protected from rusting
German silver used for decorative purposes contains maximum percentage of
-silver
-copper
-zinc
-nickel
-copper
The metals occuring at the lower most position in the electromotive series
-do not resist corrosion.
-resist corrosion very strongly.
-are very brittle.
-are heat insulators.
-resist corrosion very strongly.
German silver in an alloy of
-copper, nickel and zinc.
-copper, aluminium and silver.
-silver, zinc and aluminium.
-silver, nickel and zinc.
-copper, nickel and zinc.
A suitable material of construction to use with fuming sulphuric acid is
-carbon steel
-stainless steel type 304
-nickel
-monel
-monel
Which of the following crystal structures characterises the austenitic stainless steel?
-Simple hexagonal
-Body centred cubic
-Face centred cubic
-None of these
-Face centred cubic
Caustic soda is produced in a mercury cell having anode and cathode made respectively of moving mercury and
-moving mercury and graphite.
-graphite and moving mercury.
-moving mercury and carbon.
-moving mercury and crimped steel wire.
-graphite and moving mercury.
Addition of __________ in steel can help in increasing the depth of hardness.
-nickel
-chromium
-vanadium
-tungsten
tungsten
Which of the following has the highest compressive strength ?
-Wrought iron
-Cast iron
-Mild steel
-High carbon steel
-High carbon steel
Zinc is not used
-for producing zinc base die casting alloys.
-in its oxide form as pigments.
-as anode for corrosion prevention in boiler.
-as an alloying element in various bronzes.
-as an alloying element in various bronzes.
Refined acetic acid storage vessel are made of
-copper
-aluminium
-high carbon steel
-nickel
-aluminium
Addition of __________ to the steel helps in increasing the residual magnetism in steel used for making magnets.
-chromium
-nickel
-tungsten
-cobalt
-cobalt
Constantan is an alloy of
-Cu (55%) & Sn (45%).
-Cu (55%) & Ni (45%).
-Pt (95%) & Rh (10%).
-Fe (80%) & Ni (20%).
-Cu (55%) & Ni (45%).
Babbit metals used for making bearings are
-tin or lead based alloys.
-short of antifrictional properties.
-having homogenous microstructure.
-yellow metals.
-tin or lead based alloys.
Pipes for bi-cycle frames are made of __________ steel.
-hot rolled
-chrome carbon
-cold rolled
-stainless
-cold rolled
Which of the following materials may prove unsuitable for handling acetic acid (glacial & anhydrous) at 40°C ?
-Silicone rubber, teflon, procelain and wood.
-Nickel, monel, stainless steel and graphite.
-Aluminium, copper, high silicon iron.
-Brass, cast iron, mild steel and tin.
-Brass, cast iron, mild steel and tin.
Interchain forces are the weakest in case of
-plastics
-fibres
-elastomers
-both rubber & elastomers
-both rubber & elastomers
__________ possesses viscoelastic properties.
-Cork
-Glass
-Graphite
-Rubber
-Rubber
Steel tower used for the storage of oleum
-is lined with lead.
-need not be lined.
-is lined with rubber.
-is lined with acid-proof bricks.
-need not be lined.
Plastics are
-used in very high temperature applications.
-non-biodegradable.
-not suitable for drainage pipe manufacture.
-all (a), (b) & (c).
-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
-lead lined mild steel
-aluminium
-cast iron
-rubber lined mild steel
Wood is corroded by
-hydrochloric acid
-SO2 (dry or wet)
-chlorine (dry or wet)
-all (a), (b) and (c)
-all (a), (b) and (c)
Brass is an alloy of
-nickel and tin
-copper and zinc
-tin and lead
-copper, nickel and zinc
-copper and zinc
Lead
-is the hardest metal in common use.
-is the lightest metal in common use.
-can not be scratched by finger nails.
-can not be work hardened.
-can not be work hardened.
Photographic plates are coated with
-silver nitrate
-silver halide
-calcium silicate
-metallic silver
-silver halide
Cast iron has
-very high tensile strenth.
-high ductility.
-high malleability.
-elastic limit close to ultimate breaking strength.
-elastic limit close to ultimate breaking strength.
Locomotive boiler tubes are made of __________ alloys.
-arsenic copper
-magnesium
-aluminium
-nickel
-arsenic copper
Slow and progressive deformation of a material with time under constant stress is called
-creep
-erosion
-resilience
-none of these
-creep
Which of the following heat treatment processes is used for softening the hardened material ?
-Normalising
-Tempering
-Annealing
-None of these
-Tempering
Which of the following mechanical properties of a material is most structure insensitive ?
-Modulus of elasticity (young’s modulus).
-Toughness.
-Percentage reduction of area.
-Tensile strength.
-Modulus of elasticity (young’s modulus).
Mercury is transported in metal containers made of
-aluminium
-iron
-lead
-nickel
-iron
Which of the following would not be a suitable material of construction for handling aqueous hydrofluoric acid (HF) at 100°C ?
-Monel
-Stainless steel
-Graphite
-Kel-F and teflon
-Stainless steel
Which of the following has the least carbon percentage ?
-Low carbon steel
-Mild steel
-Wrought iron
-White cast iron
-Wrought iron
The range of Mho’s scale of hardness is from
l to l5
l to 8
l to10
0 to 10
l to10
Which of the following pairs of elements may form an alloy ?
-Iron & carbon
-Iron & mercury
-Platinum & mercury
-None of these
Iron & carbon
SO3 is absorbed using H2SO4 in a
-cast iron packed tower.
-stainless steel plate tower.
-packed steel tower lined with acid proof bricks.
-none of these.
-packed steel tower lined with acid proof bricks.
Carbon percentage in medium carbon steel is around
-0.1 to 0.35
-0.35 to 0.5
-0.8 to 1.4
-1 to 1. 5
0.35 to 0.5
The preferred material of construction for storage tanks for 98% sulphuric acid is
-aluminium
-lead
-stainless steel 316
-mild steel
-lead
The fermentor used for the production of ethyl alcohol from molasses is made of
-wood
-concrete
-copper bearing steel
-procelain
-copper bearing steel
Super conductors are those substances, which
-offer no resistance to current flow.
-conduct electricity at low temperature.
-offer high resistance to current flow.
-conduct electricity at high temperature.
-offer no resistance to current flow.
Cermets are used for making
-cutting tools
-abrasives
-both (a) & (b)
-neither (a) nor (b)
both (a) & (b)
The formation of oxide film on a metal due to atmospheric exposure reduces its
-toughness
-stiffness
-creep limit
-all (a), (b) & (c)
-creep limit
A hardened steel essentially contains
-sorbite
-troostite
-martensite
-none of these
-martensite
Which one contains the least percentage of carbon ?
-Wrought iron
-High speed steel
-Cast iron
-Pig iron
-Wrought iron
Thermal shield used in high powered nuclear reactor to protect the walls of the reactor from radiation damage is made of
-concrete
-steel
-zircalloy
-graphite
steel
All materials obey Hooke’s law within elastic limit. When elastic limit is reached, the tensile strain
-increases very quickly.
-decreases very quickly.
-increases in proportion to stress.
-decreases in proportion to stress.
-increases very quickly.
Silico-manganese steels (containing 0.7% Mn, 0.5% C and 2% Si)
-do not require heat treatment for any of its applications.
-are used for leaf and coiled springs.
-do not have good resilience properties.
-is tempered at 850°C.
-are used for leaf and coiled springs.
Which of the following is not a copper based alloy with nickel ?
-German silver
-Monel metal
-Inconel
-Constantan
Inconel
Which of the following alloys does not contain nickel ?
-Chlorinet - 2 alloy
-Monel
-Inconel
-Babbit metal
Babbit metal
An elastic behaviour of materials is expressed in terms of
-hysterisis loop area
-stress-strain curve
-relaxation time
-none of these
-relaxation time
Pure nickel is
-ferromagnetic above its curie point (i.e., 415°C).
-having h.c.p. crystal lattice.
-ferromagnetic at room temperature.
-not resistant to oxidation at high temperature.
-ferromagnetic at room temperature.
In drop forging process, the forging is done by dropping the __________ at high velocity.
-hammer
-workpiece.
-die with hammer
-weight on hammer
-die with hammer
Which of the following is not an alloy of copper and tin ?
-Bell metal
-Gun metal
-Admiralty gun metal
-Monel metal
Monel metal
__________ is never shipped in glass carboys.
-Ammonia
-Acetic acid
-Phenol
-Formaldehyde
-Ammonia
Lead is
-not resistant to corrosion.
-used as a cathodic material.
-not used as pigment (in its compound forms) for paints.
-used as a shock absorber (in mattress form) between the foundation and steel framework of skyscrapper buildings.
-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
1720
2210
910
510
Addition of 2% nickel in steel makes it suitable for making
-electronic valves
-boiler plates, rivets etc.
-turbine blades
-connecting rod
-boiler plates, rivets etc.
The softest material just next to talc in the Mhos scale is
-quartz
-gypsum
-feldspar
-fluorite
-gypsum
Fatigue strength of a material increases by
-having notches in the specimen
-rise in temperature
-under stressing the specimen
-having scratches on the surface
-under stressing the specimen
Specify the material of construction suitable for handling concentrated HNO3 at 100°C.
-High silicon iron, Kel-F and teflon
-Tin and wood
-Silicone rubber
-Stainless steel
-High silicon iron, Kel-F and teflon
Aluminium storage vessel can be used to store
-aqua regia
-ferrous sulphate
-hydrochloric acid (10%)
-none of these
-none of these
Silicone rubber is not resistant to the corrosive action of
-sulphuric acid (10%)
-sulphuric acid (95%)
-ether
-both (b) and (c)
-both (b) and (c)
Which metal is protected by the layer of its own oxide ?
-Iron
-Silver
-Calcium
-Aluminium
-Aluminium
