471. _____________ moulding process cannot be used for thermoplastic plastics?
A. Compression
B. Extrusion
C. Injection
D. None of these

472. Cast iron compared to steel is better in__________________?
A. Ductility
B. Fluidity & castability
C. Strength
D. Malleability

473. Which of the following is the hardest material ?
A. Topaz
B. Quartz
C. Corundum
D. Fluorite

474. Steel pipes are normally manufactured by ______________ process?
A. Extrusion
B. Cold working
C. Forging
D. Electroforming

475. Which of the following is the most widely used insulating material for steam carrying pipelines ?
A. Ceramic fibre blanket
B. Glass wool and 85% magnesia
C. Vermiculite
D. Slag wool

476. A metallic alloy in which one of the constituent metal is _____________, is called an amalgam?
A. Zinc
B. Mercury
C. Lead
D. Tin

477. The most distinguished property of malleable cast iron is its high_________________?
A. Ductility
B. Hardness
C. Malleability
D. None of these

478. The damage/deterioration of metals by the ______________ action of fluids is called ‘erosion’?
A. Abrasive
B. Corrosive
C. Both A. & B.
D. Neither A. nor B.

479. Steel balls for ball bearings are generally made of ______________ steel?
A. Cast
B. Stainless
C. Free carbon
D. Carbon chrome

480. Visco-elastic behaviour of materials which is time dependent is common in______________?
A. Plastics
B. Crystalline solid
C. Non-crystalline solids
D. Non-crystalline organic polymer

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