Use of gamma titanium aluminide for automotive engine valves

Abstract

Titanium aluminade is considered an interesting material for the automotive industry when applied to light hot components because of their peculiar properties.

In particular the tensile strenght which is higher in the 700-800 °C range there at room temperature.
Compared with special steel used at high temperature (21-2N) the titanium aluminide is 50% lower in density and the termal expansion is also interestihgly lower.
A suitable casting technology has been developed with the goal of having a low cost transformation process. Unalloyed TiAl has been proven adequate for automotive valves.