Question

Piston rings are plated with chromium, cadmium or phosphate in order to __________

(a) reduce cost

(b) improve surface finish

(c) prevent clogging

(d) reduce wear and eliminate scuffing

I have been asked this question during an online interview.

This interesting question is from Terminologies and Defintions in section Two Stroke Engines of IC Engine

Answer 1

Answer: (d) reduce wear and eliminate scuffing

Explanation: Piston rings are plated with materials like chromium, cadmium, or phosphate to reduce wear and eliminate scuffing. These coatings enhance the wear resistance of the rings, improve their ability to maintain a proper seal, and prevent scuffing (damage due to friction) between the piston rings and the cylinder walls, leading to better engine performance and longevity.