Properties and application characteristics of cobalt-coated tungsten carbide composite powders

       Cobalt-coated tungsten carbide composite powder is a composite powder made of WC particles as the core and cobalt as the cladding layer. The cobalt content can vary from 8% to 22%. With the increase of cobalt content, the toughness and strength of the sprayed coating increased, the crack susceptibility decreased, but the wear resistance also decreased.



    Cobalt-coated tungsten carbide composite powder coating with high hardness (HV 1300~1800) and wear resistance. Coated cobalt-coated tungsten carbide powder, the coating of metal cobalt on tungsten carbide is more complete than that of sintered tungsten carbide, so the degree of oxidative decarburization during the spraying process is relatively small, but the cost is higher.

    The fine cobalt-coated tungsten carbide composite powder with a high proportion of WC is suitable for spraying thin (about 0.2mm) wear-resistant coatings without machining.

    Since WC is prone to oxidative burnout at elevated temperature, this coating should be used as a wear-resistant coating at temperatures below 540 °C.

    Cobalt-coated tungsten carbide composite powder is most suitable for spraying high wear-resistant coatings by explosive spraying, supersonic flame spraying, controlled atmosphere plasma spraying, and vacuum plasma spraying. Gas-stabilized plasma spraying can also be used, but the oxidation burning loss of carbon is large, and the hardness and wear resistance of the coating are reduced.

    Cobalt-coated tungsten carbide composite powder is used to spray high wear-resistant coatings on high-carbon and medium-carbon steel, magnesium, aluminum, copper and its alloy substrates, with excellent resistance to low-stress abrasive wear, erosion wear, and fretting wear. and hard surface wear. Application parts such as: turbine engine fan blades, intermediate wingspan reinforcing members, tongue and groove, inhaler connecting rods; mud pump piston rods, bushings, sealing surfaces; extrusion screw, sand blasting parts; flue gas fan blades, including Sand turbine blades; drawing capstans, corrugated paper rolls, coil steel uncoiling rolls; camshafts, ratchets; cigarette machine parts, etc.