321. 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
✅ The correct answer is option B.
Materials and Construction MCQs
322. The loss of strength in compression which occurs, when there is a gain of strength in tension due to over loading is called
Bauschinger effect
Hooke’s effect
Hysterisis
Relaxation
✅ The correct answer is option A.
323. Combination of metals and ceramics are called
Metalloy
Cermets
Pellets
Non-crystalline ceramics
✅ The correct answer is option B.
324. Which of the following has a very high carbide forming tendency in steels?
Silicon
Chromium
Nickel
Vanadium
✅ The correct answer is option D.
325. Bog iron used for the adsorption of H?S from coke oven gas is
An intimate mixture of saw dust and iron dust (i.e. moist ferric hydroxide)
Iron impregnated with resin (usually bakelite)
Carbon free iron
None of these
✅ The correct answer is option A.
326. Polymerisation reactor used in the production of styrene butadiene rubber (SBR) is made of
Stainless steel or glass lined steel
Nickel clad steel
High silicon cast iron
Aluminium
✅ The correct answer is option A.
327. Coke oven regenerators are made of __________ bricks.
Fire clay
Silica
Low thermal conductivity
High electrical conductivity
✅ The correct answer is option A.
328. Materials having __________ lattice structure are usually most ductile.
F.c.c.
B.c.c.
H.c.p.
Cubic
✅ The correct answer is option A.
329. Carbon is present in steel wholly in the
Combined form
Free state as graphite
Both A & B
Neither A nor B
✅ The correct answer is option A.
330. The electrical conductivity of a __________ decreases with rise in temperature.
Metal/alloy
Semi-conductor
Dielectric
None of these
✅ The correct answer is option A.