Friction-reducing coating compositions and coated machine part

摘要

Friction-reducing coating compositions and coated machine parts having a wearing surface provided with coatings of same. In one embodiment, the coating composition includes from 10 to 25 weight % molybdenum metal; from 55 to 70 weight % nickel alloy; and from 5 to 25 weight % chromium carbide Cr3C2. In a second embodiment, the coating composition includes from 25 to 45 weight % molybdenum metal; from 45 to 60 weight % nickel alloy; and from 5 to 25 weight % of a hard substance selected from chromium metal, chromium carbide Cr23C6 and molybdenum carbide Mo2C. Preferably the nickel alloys contain from 73 to 95 weight % nickel and have a melting point below that of nickel metal. Preferably the friction-reducing coating is applied to a wearing surface by plasma flame spraying. These coatings impart excellent wear resistance to the wearing surface, while lowering wear of counter-running faces.