Oxidation Resistance of Transient Liquid Phase (TLP)-Bonded Gamma Titanium Aluminide

摘要

One of the challenges in the application of titanium-aluminide materials for high-temperature components in aerospace gas turbine engines is the development of suitable joining techniques, which are required for the fabrication of some large and/or complicated shapes. Recently, Transient Liquid Phase (TLP) bonding using a copper-containing composite interlayer has been used successfully to bond Ti-48Al-2Nb-2Cr. The TLP bond region has the same microstructure as that of the base alloy, but contains small amounts of copper. The oxidation resistance of titanium aluminide alloys can be significantly affected by small alloying additions. Fortunately, studies of the oxidation behavior of Ti-48Al-2Nb-2Cr with copper additions have shown that the amounts of copper in the TLP bond regions are not detrimental to the oxidation resistance of the alloy. In this paper, results of studies on the oxidation behavior of TLP-bonded Ti-48Al-2Nb-2Cr will be presented and considerations in selection of materials for use in oxidation resistant bonds of titanium-aluminide alloys will be discussed.