Abstract: A TiAl intermetallic compound-base alloy material having excellent strength properties at high temperatures and ductility, characterized by comprising: a fine alumina (Al.sub.2 O.sub.3) dispersed so as to give an O.sub.2 concentration of 1000 to 5000 ppm by weight and in a particle diameter of 200 to 500 nm; a boride (TiB.sub.2) dispersed to give a B concentration of 0.1 to 10 at % and in a particle diameter of not more than 500 nm; 1 to 3 at % of at least one of Cr, Mn, and V; and TiAl having a Ti content of 50 to 53 at % and an Al content of 47 to 50 at %, said TiAl intermetallic compound-base alloy material having been directly cast at a cooling rate of 10.sup.3 to 10.sup.5 .degree. C./sec and a process for producing the same. According to the present invention, exhaust valves for automobiles and materials for engine turbines for jet airplanes and the like having excellent tensile strength at high temperatures and ductility at high temperatures and room temperature are provided.

Abstract: This invention relates to TiAl based intermetallic compound alloy and process for producing; the object of this invention is to improve high temperature deformability. The alloy comprises basic components: Ti.sub.y AlCr.sub.x, wherein 1%.ltoreq.X.ltoreq.5%, 47.5%.ltoreq.Y.ltoreq.52%, and X+2Y.gtoreq.100%, and comprises a fine-grain structure with a .beta. phase precipitated on a grain boundary of equiaxed .gamma. grain having grain size of less than 30 .mu.m, and possessing a superplasticity such that the strain rate sensitivity factors (m value) is 0.40 or more and tensile elongation is 400% or more tested at 1200.degree. C. and a strain rate of 5.times.10.sup.-4 S.sup.-1.

Abstract: This invention relates to TiAl based intermetallic compound alloy and process for producing; the object of this invention is to improve high temperature deformability. The alloy comprises basic components: Ti.sub.y AlCr.sub.x, wherein 1%.ltoreq.X.ltoreq.5%, 47.5%.ltoreq.Y.ltoreq.52%, and X+ 2Y.gtoreq.100%, and comprises a fine-grain structure with a .beta. phase precipitated on a grain boundary of equiaxed .gamma. grain having grain size of less than 30 .mu.m, and possessing a superplasticity such that the strain rate sensitivity factors (m value) is 0.40 or more and tensile elongation is 400% or more tested at 1200.degree. C. and a strain rate of 5.times.10.sup.-4 S.sup.-1.