MECHANICAL AND MICROSTRUCTURAL RESPONSE OF NEAR BETA Ti ALLOYS TO HOT TENSILE TESTING

作者：Abbasi S M; Momeni A; Daraee M; Akhondzadeh A; Mirsaeed G

来源：Archives of Metallurgy and Materials, 2017, 62(2): 815-823.

DOI：10.1515/amm-2017-0121

<jats:title>Abstract</jats:title>
<jats:p>Hot tensile tests were carried out on Timetal-125 and Timetal-LCB near beta Ti alloys at temperatures in range of 600-1000°C and constant strain rate of 0.1 s<jats:sup>−1</jats:sup>. At temperatures below 700-800°C, the homogenuous and total strains for Timetal-LCB were greater than those for Timetal-125. In contrast, at temperatures over 800°C, Timetal-125 showed better hot ductility. The yield point phenomena was observed in Timetal-LCB at all temperatures. Unlikely, for Timetal-125, it was observed only at temperatures over 800°C. The weaker yield point phenomena in Timetal-125 could be attributed to the negative effect of Al on the diffusion of V. At all temperatures Timetal-LCB exhibited higher strength than Timetal-125. It was found that there should be a direct relationship between the extent of yield point phenomena and strength and dynamic softening through hot tensile testing. It was observed that at temperatures beyond 800°C (beta phase field in both alloys) dynamic recrystallization can progress more in Timetal-125 than in Timetal-LCB. These results were in good agreement with the better hot ductility of Timetal-125 at high temperatures. At low temperatures, i.e. below 700-800°C, partial dynamic recrystallization occurs in beta and dynamic globularization in alpha phase. These processes progress more in Timetal-LCB than in Timetal-125.</jats:p>

• 出版日期2017-6