Which of the following pipes is least corrosion resistant?
Brass
Mild steel
Cast iron
Wrought iron
Correct Answer :
D. Wrought iron
Related Questions
Austenite is a combination of
Ferrite and cementite
Cementite and gamma iron
Ferrite and austenite
Ferrite and iron graphite
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
Iron-carbon alloys containing 1.7 to 4.3% carbon are known as
Eutectic cast irons
Hypoeutectic cast irons
Hypereutectic cast irons
None of these
Machining properties of steel are improved by adding
Sulphur, lead, phosphorous
Silicon, aluminium, titanium
Vanadium, aluminium
Chromium, nickel
Connecting rod is usually made of
Aluminium
Low carbon steel
Medium carbon steel
High carbon steel
Cartridge brass can be
Cold rolled into sheets
Drawn into wires
Formed into tube
Any one of these
The alloying element which increases residual magnetism and coercive magnetic force in steel for magnets is
Chromium
Nickel
Vanadium
Cobalt
When the steel is normalised, its
Yield point increases
Ductility decreases
Ultimate tensile strength increases
All of these
The brown smoke during the operation of a Bessemer converter indicates that the
Air is burning out silicon and manganese
Silicon and manganese has burnt and carbon has started oxidising
The converter must be titled to remove the contents of the converter
The brown smoke does not occur during the operation of a Bessemer converter
The compressive strength of cast iron is ________ that of its tensile strength.
Equal to
Less than
More than
None of these
The carbon in the pig iron varies from
0.1 to 0.5 %
0.5 to 1 %
1 to 5 %
5 to 10 %
The alloy, mainly used for corrosion resistance in stainless steels is
Silicon
Manganese
Carbon
Chromium
Blast furnace produces following by reduction of iron ore
Cast iron
Pig iron
Wrought iron
Malleable iron
Monel metal is an alloy of
Nickel and copper
Nickel and chromium
Nickel, Chromium and iron
Copper and chromium
The percentage of carbon in cast iron varies from
0.1 to 0.5
0.5 to 1
1 to 1.7
1.7 to 4.5
Addition of silicon to aluminium results in
Improvement of casting characteristics
Improvement of corrosion resistance
One of the best known age and precipitation hardening systems
Improving machinability
Pipes for bicycle frames are made of
Cold rolled steel
Hot rolled steel
Forged steel
Cast steel
Tungsten when added to steel ________ the critical temperature.
Does not effect
Lowers
Raises
None of these
The basic constituents of Hastelloy are
Aluminium, copper etc.
Nickel, molybdenum etc.
Nickel, Copper, etc.
All of the above
Permalloy is a
Kind of stainless steel
None ferrous alloy
Polymer
Nickel and iron alloy having high permeability
The ability of a material to resist fracture due to high impact loads, is called
Strength
Stiffness
Toughness
Brittleness
Connecting rod is, usually, made from
Low carbon steel
High carbon steel
Medium carbon steel
High speed steel
The ability of a material to absorb energy in the plastic range is called
Resilience
Creep
Fatigue strength
Toughness
Isotropic materials are those which have the same
Elastic properties in all directions
Stresses induced in all directions
Thermal properties in all directions
Electric and magnetic properties in all directions
Perminvar alloy having constant permeability is an alloy of
Nickel, copper and iron
Nickel, copper and zinc
Copper, nickel and antimony
Iron, zinc and bismuth
Which is the false statement about wrought iron? It has
High resistance to rusting and corrosion
High ductility
Ability of hold protective coating
Uniform strength in all directions
Which of the following statements are true for annealing of steels?
Steels are heated to 500 to 700°C
Cooling is done slowly and steadily
Internal stresses are relieved
All of these
Steel made from phosphate iron is
Brittle
Hard
Ductile
Tough
Melting point of iron is
1539°C
1601°C
1489°C
1712°C
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