Which of the following class of engineering ceramics generally includes lubricant materials?

Mechanical Engineering : Engineering Materials - Quiz(MCQ)

Carbides

Metalloids

Sulphides

Intermetallics

Correct Answer : Option (C) : Sulphides

Explanation : Molybdenum disulfide (MoS2) and tungsten disulfide (WS2) are common sulfide materials used in lubrication. Metalloid elements like germanium and silicon are used as electronic devices. Intermetallics like Nickel aluminide are used in water coatings.

Recently Updated in Engineering Materials Questions

Babbit metal contains

92% tin, 6% copper and 2% antimony

88% tin, 4% copper and 8% antimony

66% tin, 30% copper and 4% antimony

50% tin and 50% antimony

Correct Answer : 88% tin, 4% copper and 8% antimony

What is the result of full annealing of hypoeutectoid steels?

Bainite

Silicon

Cementite

Coarse pearlite

Correct Answer : Coarse pearlite

Explanation : Hypoeutectoid steels are heated above the A3 line and then cooled in the furnace. Then it removed from the furnace and then cooled at room temperature. This results in coarse pearlite with excess ferrite.

A fine grained steel

is less tough and has a less tendency to distort during heat treatment

is less tough and has a greater tendency to distort during heat treatment

is more ductile and has a less tendency to distort during heat treatment

is more ductile and has a greater tendency to distort during heat treatment

Correct Answer : is more ductile and has a less tendency to distort during heat treatment