Accession Number : AD0768404

Title :   Microstructure and Phase Relations for Ti-Mo-Al Alloys.

Descriptive Note : Technical rept. 1 Oct 70-30 Sep 71,

Corporate Author : RUTGERS - THE STATE UNIV NEW BRUNSWICK N J MATERIALS RESEARCH LAB

Personal Author(s) : Hamajima,T. ; Lutjering,G. ; Weissmann,S.

Report Date : NOV 1971

Pagination or Media Count : 22

Abstract : The influence of aluminum additions to a titanium-7 at % molybdenum alloy on the phase equilibria was investigated. The microstructures of the alloys, Ti-7% Mo-7% Al, and Ti-7% Mo-16% Al, were determined by light and electron microscopy. It was found that with increasing aluminum concentration the formation of the metastable omega phase was suppressed. In the Ti-7% Mo-16% Al alloy the beta phase decomposed upon quenching by precipitating coherent, ordered particles having a CsCl type of crystal structure (beta sub 2). At low temperatures the equilibrium phases for this alloy were beta + alpha + beta sub 2, whereas at high temperature (850C-950C) the Ti3Al phase was in two-phase equilibrium with the beta phase. The four-phase equilibrium which exists at a temperature of about 550C involves the reaction beta + Ti3Al reversibly yield alpha + beta sub 2. (Author)

Descriptors :   (*TITANIUM ALLOYS, PHASE STUDIES), MOLYBDENUM ALLOYS, ALUMINUM ALLOYS, MICROSTRUCTURE, THERMAL STABILITY, DIFFUSION

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE