中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 25 No. 9 September 2015 |
(1. National Key Laboratory for Precision Hot Processing of Metals, School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China;
2. State Key Laboratory of Nonferrous Metals and Processes, BeijingGeneral Research Institute for Nonferrous Metals, Beijing 100088, China)
Abstract:Thehydrogen-induced microstructure evolution and phase transformations in Ti-6Al-4V alloy during heating and cooling were studied. The specimens were heated to 1273K and subsequently cooled to room temperature. The hydrogen content is up to 0.8% (mass fraction). The hydrogen-induced dynamic phase transformations and the corresponding mechanisms were analyzed. When the hydrogen content increases, the β transus temperature significantly decreases and the magnitude decreases, and the volume fraction of β phase increases. During heating, the phase transformations in hydrogenated Ti-6Al-4V alloys can be divided into three stages, and the phase transformation order is δ→α+H2↑?δ+α′→βH?α′→αH+βH?αH→α+H2↑?α→β?βH→β+H2↑. In addition, the relationship among hydrogenation and Ms and Mf of α′ martensite were determined.
Key words: titanium alloy; phase transformation; hydrogen; in situ