Effects of zirconium addition on microstructures and mechanical properties of Co-29Cr-6Mo alloy

Abstract

Co-29Cr-6Mo alloys consisting of 0-1.76% Zr were prepared and heat-treated at 1210°C for 2h or 1230°C for 3h. Three types of precipitates were identified. With more than 0.37% Zr content, precipitates are mixtures of a phase and (Zr, Mo)-rich phase. The α phase dissolves into a matrix and the (Zr, Mo)-rich phases change its composition into a Zr-rich phase with heat treatment. An alloy with a solid solution containing 0.01% Zr exhibits improved mechanical properties. © 2007 The Japan Institute of Metals.