An alloy of titanium - aluminum intermetallic compounds with good high temperature properties and a process for their preparation

摘要

A Ti-Al intermetallic compound alloy material which is superior in strength at high temperatures and ductility and a method for producing the same comprising the steps of dispersing fine alumina (Al2O3) at an O2 concentration of 1000-5000 wt.ppm and with a particle diameter of 200∩500 nm and boride (TiB2) at a B concentration of 0.1∩10 at % and with a particle diameter of 500 nm or less, adding 1-3 at % of one or two or more of Cr, Mn and V, and direct casting them at a cooling speed of 10?3∩105¿ °C/sec, the resulting product containing 50∩53 at % of Ti and 47∩50 at % of Al. The present invention can provide a material for automobile exhaust valves and jet engine turbines which is superior in tensile strength at high temperatures and ductility at room and high temperatures.