New doped alloys on tre base of Li₂ intermetallic of Al—Ti—Cr system withi increased level of oxidation resistance

Abstract

Influence of one-element (Zr, Hf, Sc, Y and Si) and complex (ScSi, ScSiZr, ScZrHf, SiYHf) alloying on oxidation resistance of one- and two-phase eutectic alloys with participation of L1₂ intermetallic of ternary Al—Ti—Cr system has been investigated. Alloying elements that increase the oxidation resistance of these groups of alloys at temperatures 800—1100^оС have been determined. It was shown that Hf is the most effective alloying element for increase the oxidation resistance of one-phase L1₂ intermetallic, but Zr and Si are the most effective for eutectic alloy. Sc is the element that increases the properties of the two types of alloys. Among the complexes of alloying elements (0,1Sc0,2Zr0,2Hf) complex turns out to be the most effective for alloys on the base of one-phase L1₂ intermetallic, but (0,1Sc0,5Si0,2Zr)complex turns out to be the most effective for eutectic (L1₂ + β) alloys. It was shown the advantage by oxidation resistance of new alloys in comparison with industrial 48Ti—2Nb—2Cr (γ-TiAl) alloy. Full text download