Effect of tin addition on the microstructure, wettability and mechanical properties of Cu–Mn–Ni braze fillers

Abstract

A series of Cu–34Mn–6Ni–[Formula: see text]Sn (wt.%) braze fillers that were used for brazing stainless steel (SS) were prepared. The microstructures, melting temperatures, wettability and mechanical properties of the braze fillers were investigated. An Sn-rich phase was formed in braze fillers with an Sn content above 6 wt.% (including) because of the segregation performance of Sn. The melting temperatures of braze fillers decreased markedly with an increase in Sn content. The addition of 6 wt.% Sn resulted in the highest wettability of braze fillers on the SS. With an increase in Sn content, the tensile strength and hardness increased, whereas the plasticity and toughness of the braze fillers decreased owing to the solid solution and segregation of Sn.