For mechanical applications where mating parts move against each other under high loads, such as shaft/bushing pairs, the mating surfaces of each will typically be coated or treated to increase the hardness of the mating surfaces, thereby improving wear resistance.
Surface treatments primarily employed to increase wear resistance usually have the added benefit of decreasing the friction between the two parts. PVD coatings create an exceptional finish with very low surface roughness values so that the friction between the parts is as low as possible, creating wear resistance therefore lasting longer.
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