Abrasion and impact resistant coatings

摘要

A method of hard facing a metal substrate with a two-layer abrasion and impact resistant coating by fusing a softer inner first coat of a matrix alloy of nickel-, cobalt- or iron-base alloy with carbide particles onto the substrate and fusing a harder second outer coat of a matrix alloy of nickel-, cobalt- or iron-base alloy with angular carbide particles onto the softer inner first coat. The softer inner first coat preferably has a hardness of about 30-40 Rc and the harder outer second coat preferably has a hardness of about 50-60 Rc. The carbide particles preferably are tungsten carbide particles in the size range of about 60 to 250μ and comprise about 55 to 65 wt % of each of the inner and outer coats.