1834. Gun metal is an alloy of
Nickel, tin and copper
Copper, tin and zinc
Copper, phosphorus and nickel
Manganese, phosphorus and nickel
✅ The correct answer is option B.
1797. High speed cutting tool steels contain about __________ percent of tungsten.
6-Aug
18-20
30-35
50-55
✅ The correct answer is option B.
1800. Hardening of steel is not possible unless it is heated __________ critical point.
Above the highest
Above the lowest
Between the first & second
Between the second & third
✅ The correct answer is option B.
1803. Galvanising is not a zinc diffusion process. A zinc diffusion process is termed as
Sheradising
Parkerising
Anodising
None of these
✅ The correct answer is option A.
1806. Ball bearings are normally made of __________ steel.
High speed
High carbon
Chrome
Silicon
✅ The correct answer is option C.
1809. The formation of oxide film on a metal due to atmospheric exposure reduces its
Toughness
Stiffness
Creep limit
All of the above
✅ The correct answer is option C.
1812. Tin vessels are corroded by
Anhydrous ammonia
Aromatic solvents
Synthetic detergent solution
None of these
✅ The correct answer is option D.
1815. Corrosion resisting properties of cast iron are significantly improved by the addition of 12 – 15% of
Tungsten
Vanadium
Silicon
All of the above
✅ The correct answer is option C.
1818. Evaporators used in caustic soda recovery and production plant are made of
Monel metal
Gun metal
Wood metal
Babbit metal
✅ The correct answer is option A.
1771. Telfon (PTFE) is corroded by
Hydrochloric acid (10%)
Hydrochloric acid (95%)
Sulphuric acid
None of these
✅ The correct answer is option D.