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

An investigation of microstructural development and structure-property relationships of transient liquid phase (TLP) bonded current generation gamma-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 gamma-TiAl alloy, Ti-48Al-2Cr-2Nb (at.-%), and wide gap TLP bonding of Gamma Met PX.