These results showed that wear rate of hardened, tufftrided, titanium nitride and chromium carbide coated, boronized and vanadium carbide coated AISI 52100 steel balls coated by thermo-chemically steel were approximately linearly proportional to load. The contacting AISI 52100 steel ball showed even greater wear rate when tested on the titanium nitride coated AISI 1020 steel samples from thermo-chemically coated AISI 52100 steel samples