Transient liquid phase bonding of Gamma Met PX: microstructure and mechanical properties

Abstract

An investigation of microstructural development and structure–property relationships of transient liquid phase (TLP) bonded current generation γ-TiAl alloy, known as Gamma Met PX, is presented. This joining technique employed a composite interlayer consisting of a non-melting constituent (TiAl alloy) and a liquid forming constituent (copper). The microstructures of the bonds, identified using light microscopy and scanning electron microscopy, are correlated with room temperature mechanical performance. These studies suggested that joints can retain properties similar (i.e. >90%) to that of the bulk material when employing a suitable composite interlayer, bonding conditions and post-bond heat treatment. Additionally, comparisons are drawn between wide gap TLP bonding of an earlier generation γ-TiAl alloy, Ti–48Al–2Cr–2Nb (at.-%), and wide gap TLP bonding of Gamma Met PX.