EFFECTS OF OXYGEN AND OXIDATION ON TENSILE BEHAVIOR OF V-4CR-4TI ALLOY

Vanadium-base alloys are potential candidates for applications such as the first wall and other structural components of fusion reactors, bu t a good understanding of the oxidation behavior of the alloys intende d for elevated-temperature use is essential. We conducted a systematic study to determine the effects of time and temperature of air exposur e on the oxidation behavior and microstructure of V-4Cr-4Ti alloy. Uni axial tensile tests were conducted at room temperature and at 500 degr ees C on preoxidized specimens of the alloy to examine the effects of oxidation time and oxygen migration on maximum engineering stress and uniform and total elongation. The effect of preexposure of the specime ns to environments with varying oxygen partial pressures on the tensil e properties of the alloy was investigated. Extensive microstructural analyses of the oxygen-exposed/tensile-tested specimens were conducted to evaluate the cracking propensity for the alloy. In addition, tensi le-property data for the alloy were correlated with oxygen pressure in the exposure environment, test temperature, and exposure time. (C) 19 98 Elsevier Science B.V. All rights reserved.