Accession Number : ADA331063

Title :   Hydrogen Effects on Some Titanium Aluminides at Ambient Temperature, Tri-Service Committee on Corrosion Proceedings

Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC MATERIAL SCIENCE AND TECHNOLOGY DIV

Personal Author(s) : Smith, James A.

PDF Url : ADA331063

Report Date : JUN 1994

Pagination or Media Count : 14

Abstract : It is common to describe the corrosion damage of structural metals and alloys in terms of the eight basic types of metal/alloy corrosion: general corrosion, galvanic corrosion, crevice corrosion, pitting attack, erosion corrosion, selective leaching, intergranular corrosion, and environmental assisted fracture. The latter, environmental assisted fracture, may be further divided into subheadings of stress corrosion cracking, corrosion fatigue, and hydrogen embrittlement. Of particular interest is hydrogen embrittlement because of the serious problems and/or catastrophic failures that may result from the involvement of structural materials such as titanium and titanium alloys with hydrogen. Previous investigators have shown that Ti-6Al-4V and indeed most conventional titanium alloys are susceptible to hydrogen embrittlement in hydrogen charging environments (22). Titanium aluminides, the materials studied in this report, are also believed to be subject to hydrogen embrittlement but preliminary studies show that the gamma based aluminides may be less prone to absorbing hydrogen at ambient and elevated temperatures than conventional Ti alloys (21). The major draw for use of these materials is the fact that they possess outstanding high-temperature strength, good creep behavior and low density. Possession of these characteristics has warranted their consideration for a wide range of applications from automotive turbo charger motors, pistons, and valve material to advanced aerospace applications involving temperatures up to 1045 deg C. Therefore, it is important to ascertain their hydrogen embrittlement behavior if hydrogen-related property damage is to be understood and, hopefully, controlled in these materials.

Descriptors :   *SYMPOSIA, *TITANIUM ALUMINIDE, *HYDROGEN EMBRITTLEMENT, POLARIZATION, MICROSTRUCTURE, CORROSION, HIGH STRENGTH ALLOYS, LOW DENSITY, STRESS CORROSION, TITANIUM ALLOYS.

Subject Categories : Properties of Metals and Alloys
      Test Facilities, Equipment and Methods

Distribution Statement : APPROVED FOR PUBLIC RELEASE