Joining of Intermetallice Compound TiAl by using Al Filler Metal

Abstract

Ti-34 mass% Al cast alloy with γ-(TiAl)/α 2 (Ti 3 Al) lamellar structure was bonded at 1173 K by using Al sheet as a filler metal. At 1173 K, Al filler metal melted and reacted with base metal to transform to TiAl 3 or TiAl 2 by the diffusion of Ti from base metal. By the subsequent heat treatment of the joint at 1573 K, TiAl joint was homogenized and the filler metal transformed to single γ phase. The obtained TiAl joint had almost the same tensile strength as that of base metal, 220 MPa, at room temperature or at 873 K