Question

How does the amount of cobalt affect the wear of alloys?

(a) High cobalt high wear

(b) Low cobalt high wear

(c) No cobalt high wear

(d) Cobalt does not affect the wear

The question was asked in unit test.

Question is taken from Metal Spraying and Hard Facing, Age Hardening topic in portion Wear of Metals, Mechanical Properties and Testing of Engineering Material & Metallurgy

Answer 1

Right option is (a) High cobalt high wear

Best explanation: Higher cobalt concentration of about 13-17% results in 30-40% faster wear or the alloys. However, it provides better resistance to mechanical shock. The basic tungsten-carbide composition containing 6-8% cobalt is recommended for general wear applications.