Weldable, crack-resistant co-based alloy, overlay method, and components

摘要

A wear- and corrosion-resistant alloy, and related application method, where the alloy has by approximate weight %, C 0.12-0.7, Cr 20-30, Mo 7-15, Ni 1-4, and Co balance, wherein the alloy further contains one or more carbide-former elements from the group consisting of Ti, Zr, Hf, V, Nb, and Ta in a cumulative concentration to stoichiometrically offset between about 30% and about 90% of the C in the alloy.

主权项

1. A wear-and corrosion-resistant alloy for forming a weld overlay over a metallic component, the alloy consisting of, by approximate weight %:C0.2-0.4Cr22-27Mo11-14Ni3-4CoBalanceSiup to about 1Mnup to about 1Feup to about 1Wup to about 1B + Cuup to about 3 wherein the alloy further contains Nb as a carbide-former in a concentration to provide a weight ratio of Nb to C between 2.3:1 and 7:1 to stoichiometrically offset between about 30% and about 90% of the C in the alloy, such that Nb is consumed in the formation of carbides and is not available for formation of brittle intermetallic phases and such that carbon is thereby consumed by Nb in the formation of Nb carbides, which carbon is therefore unavailable to consume Mo and Cr by formation of Mo and Cr carbides; and wherein the alloy has an electron vacancy number between 2.3 and 2.80 as calculated using SAE specification AS5491 (Revision B), with no contribution from the carbide-former element.