A. Removed by acid pickling
B. Hammered into the surface
C. Removed with coarse emery cloth
D. Left as such to protect the surface
Related Mcqs:
- Transformation range for ferrous material is the temperature interval during which ___________________ is formed during its heating?
A. Cementite
B. Austenite
C. Martensite
D. Pearlite - Solidification time of a molten metal in a casting is proportional to (where, V = volume of metal & A = its surface area; in the casting) ?
A. V/A
B. V/A2
C. V2/A
D. V2/A2 - _______________ is the trade name assigned to a non-ferrous cast alloy composed of cobalt, chromium & tungsten ?
A. Stellite
B. High speed steel
C. Cermet
D. Alnico - Non-ferrous alloys used for making cutting tools need not have high__________________?
A. Abrasion resistance
B. Toughness
C. Red hardness
D. Cutting speed - _________________ furnace is generally used in the non-ferrous foundries ?
A. Direct arc
B. Indirect arc
C. Resistance
D. Induction - _____________ is the process of coating the surface of steel with aluminium oxide, thereby imparting it increased resistance to corrosion & oxidation upto a temperature of 700°C ?
A. Veneering
B. Galvanising
C. Electroplating
D. Calorising - Which of the following materials does not form adherent oxide film on surface ?
A. Copper
B. Nickel
C. Aluminium
D. Gold & silver - With increase in annealing temperature, the following defect density decreases?
A. Vacancy
B. Dislocation
C. Grain boundary
D. All of these - Annealing of white cast iron produces _____________________ iron?
A. Grey
B. Nodular
C. Malleable
D. Spheroidal - ______________________ iron is produced by the annealing of white cast iron?
A. Malleable
B. Nodular
C. Ductile
D. Grey
