Abrasion and corrosion resistant cobalt base alloys for hardfacing

Previous investigations carried out at CRM have shown that adding Mo, singly or in combination with Ni and/or Cu, enhances greatly the corrosion and abrasion resistance of high-carbon Co-Cr-W-C cast alloys.On account of these improvements, coatings of several Mo-, Ni- and/or Cu-modified grades of a Co-2.2% C-13% W-32% Cr alloy were prepared either by oxyacetylene welding with cast electrodes or by plasma spraying with prealloyed powders. The abrasion/corrosion behavior of the experimental deposits was compared with that of commercial alloys. The test data reported in this paper reveal the particularly good behaviour of the 18.2% Ni-4% Cu-8.7% Mo modified grade.