Accession Number : AD0801472

Title :   A STUDY OF THE CRYSTAL STRUCTURE OF TI-AL ALLOYS AND HYDROGEN INDUCED EXPANSIONS.

Descriptive Note : Final rept. 1 Jan 64-30 Sep 65,

Corporate Author : NEW YORK UNIV NY ENGINEERING RESEARCH DIV

Personal Author(s) : Portisch, H. ; Margolin, H.

Report Date : SEP 1966

Pagination or Media Count : 91

Abstract : The structure of a Ti-Al phase reported on gamma Ti3Al has been found by single crystal x-ray studies to be alpha Ti with superlattice spots of Ti3Al. A surface expansion, found to occur after etching alloys containing 9.5-12.5 wt% Al, occurs as a result of hydrogen picked up by etching. It is proposed that hydrogen initially enters octahedral sites of Ti3Al coherent with alpha Ti and later shifts to the tetrahedral sites. It is postulated that expansion occurs when the hydrogen enters the tetrahedral sites. (Author)

Descriptors :   (*TITANIUM ALLOYS, ALUMINUM ALLOYS), CRYSTAL STRUCTURE, SINGLE CRYSTALS, HYDROGEN, MICROSTRUCTURE, X RAY DIFFRACTION, TEMPERATURE, ETCHED CRYSTALS, ETCHING, DENSITY, HEAT TREATMENT.

Subject Categories : Properties of Metals and Alloys
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE