Effects of Oxygen and Nitrogen Addition on Phase Transformation in Ti-10at%V

Abstract:

The addition of oxygen or nitrogen in titanium alloys increases the hardness by the solid solution strengthening. Spinodal decomposition in titanium alloys is also the way to increase the hardness. This study aimed to reveal the effect of oxygen or nitrogen addition on spinodal decomposition in Ti-10at%V. Ti-10at%V-(0, 1, 3)at%O or N alloys were prepared by arc-melting. They were solution-treated at 1200 or 1300 °C for 0.6 ks and then quenched in iced brine. The solution treated specimens were aged at 375 °C. The increase of hardness was decreased by the oxygen or nitrogen addition in the alloys. The addition of nitrogen more suppressed the age-hardening than the case of oxygen addition. The modulated structure caused by spinodal decomposition in the laths was observed in all the aged specimens. The wavelength of spinodal decomposition of the aged specimens increased with the addition of oxygen or nitrogen, leading to a decrease in age-hardening by spinodal decomposition.

• Periodical: Materials Science Forum (Volume 985)
• Pages: 80-85
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.985.80
• Online since: April 2020
• Authors: Sengo Kobayashi*, Ryohei Fukushima, Siqi Wu, Satoshi Okano
• Keywords: Aging, High Hardness, Nitrogen, Oxygen, Spinodal Decomposition, Ti Alloy

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