Research on Law and Mechanism of Hydrogen Induced Softening in Ti6Al4V Alloy in the Temperature Range 400 °C to 1010 °C

Abstract:

The law and mechanism of hydrogen induced softening in Ti6Al4V alloy in the temperature range 400 °C to 1010 °C are researched by lots of isothermal hot compression experiment in this paper. The relationship between σ_h (the true stress when the test is compressed to half of its original height) and C_H (hydrogen content) is investigated to describe the law. The results show that, Between 400 °C and 450 °C, the plasticity increases at first, and then decreases and the strength is almost changeless with the C_H rising. Between 480 °C and 950 °C, the strength decreases at first, and then increases with the C_H rising. In α+β phase region, the strength decreases with the C_H rising. In β phase region, the strength increases with the C_H rising. Hydrogenation induced α phase high temperature softening and hydrogenation promoting α→β phase transition are the main reasons for hydrogen induced titanium alloy softening. Hydrogenation induced β phase solution strengthening is the reason for hydrogen induced titanium alloy strengthening. And the relationship between furnace temperature and vacuum is investigated during dehydrogenation heat treatment.

• Periodical: Advanced Materials Research (Volumes 1120-1121)
• Pages: 1202-1207
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1120-1121.1202
• Online since: July 2015
• Authors: Shu Hui Huang*, Ying Ying Zong, De Bin Shan
• Keywords: Hydrogen, Softening, Ti6Al4V

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