The product of a commercial direct reduction process is
Liquid iron
Solid iron
Sponge iron
Iron saturated with carbon
Correct Answer :
C. Sponge iron
Related Questions
Non-ferrous alloys used for making cutting tools need not have high
Abrasion resistance
Toughness
Red hardness
Cutting speed
Electrolytic reduction cell used for conversion of calcined Al2O3 to Al is a carbon lined furnace operating at 800-900 °C. The purpose of electric current supplied to the furnace is to
Achieve very high purity of aluminium (99.9%)
Keep the electrolyte in liquid condition by the generation of heat
Electrolytically dissociate alumina
Both (B) & (C)
The swift cup test evaluates the following property of a sheet metal.
Stretchability
Drawability
Bendability
None of these
Which of the following metals is the most prone to work hardening?
Brass
Aluminium
Copper
Lead
Dislocation cross-slip is difficult in those materials, which have
Large number of slip systems
High work hardening rate
Coarse grain size
Low stacking fault energy
Solidification time of a molten metal in a casting is proportional to (where, V = volume of metal & A = its surface area; in the casting)
V/A
V/A2
V2/A
V2/A2
Out of the following, the lowest packing of atoms exists in __________ crystal lattice structure.
Hexagonal close, packed (hcp)
Face centred cubic (fcc)
Body centred cubic (bcc)
Simple cubic
Thermal efficiency of an internal combustion engine is around __________ percent.
8
35
65
80
__________ is the process used for setting up compressive stresses in the surface of a metal to improve its fatigue strength.
Lancing
Shot peening
Slugging
Spinning
The best guide to judge the general quality of water is the measurement of its
pH value
Electrical conductivity
Turbidity
Dissolved oxygen content
Which of the following gases cause global warming?
Carbon monoxide
Carbon dioxide
Nitrogen
Ozone
The ratio of mass of a neutron to that of an electron is about 1839. What is the ratio of the mass of a proton to that of an electron?
159
1837
2537
10000
Out of the following, the most malleable material is
Copper
Aluminium
Wrought iron
Lead
With increase in annealing temperature, the following defect density decreases.
Vacancy
Dislocation
Grain boundary
All of these
To improve the machinability of steel, it is generally subjected to
Spheroidising
Tempering
Normalising
Annealing
CANDU type nuclear reactor using natural uranium as fuel is the extensively used nuclear reactor because of the fact that the
Specific fuel consumption is very low due to the use of heavy water
Fuel cost is much lower than that used in pressurised water or boiling water reactor
Heavy water is used both as coolant as well as moderator
Both 'b' & 'c'
In a boundary layer developed along the flow, the pressure decreases in the downstream direction. The boundary layer thickness in this case will
Decrease gradually
Increase gradually
Increase rapidly
Remain constant
Young's modulus of a material is the measure of its
Stiffness
Malleability
Creep resistance
Tensile strength
Pick out the wrong statement about the machinability of metals. Machinability of a metal
Decreases with increase in strain hardening tendencies
Decreases with increase in hardness, in general
Depend on the composition, microstructure and physical & mechanical properties
Decreases with increases in tensile strength & decrease in grain size
Pick out the wrong statement.
Copper is the metal having the highest electronic conductivity
Hardenability & Weldability of metals are inversely related
Covalent bonding formed by sharing of electrons is present in all semi-conductor materials
Glass transition temperature applies to 'polymers' but not to 'glasses'
Pick out the wrong statement.
Complete unity of command exists in a line organisation
Line organisation is net suitable for expansion and growth of an industry
In line and staff organisation, line executes and staff directs
None of these
Other parameters remaining same, the recrystallisation temperature of an alloy is lowered, when
Strain rate is increased
Grain size is increased
Prior cold deformation is increased
Not affected by any of the above parameters
The main reducing agent in iron blast furnace is
Carbon dioxide
Carbon monoxide
Oxygen
Air
Minimum temperature upto which water can be theoretically cooled down in the cooling tower by evaporative cooling is equal to the __________ temperature of air.
Wet bulb
Dry bulb
Saturation
Dew point
In the diving apparatus, helium is used along with oxygen, because it is
Easily available
Not soluble in blood at high pressure
Lighter than nitrogen
Completely miscible with oxygen
Alloys having more than 80% copper are generally more
Abrasion resistant
Corrosion resistant
Prone to season cracking
Machinable
Dielectric
Is an electrical insulating material
Of low resistivity is preferred
Should have high thermal conductivity
Need not defy the corrosive action of chemicals
Spheroidising of a material is a/an __________ process.
Normalising
Annealing
Tempering
Hardening
Which of the following is not categorised as the ore agglomeration process?
Nodulising
Pelletising
Balling
Briquetting
As the fluid flow rate increases, the float of the Rotameter
Rises in the tube
Rotates at higher speed
Rotates at lower speed
Drops down in the tube