(1. 北京航空材料研究院 鈦合金研究室, 北京100095;
2. Rolls-Royce Plc, P.O.Box 31, Derby DE24 8BJ, UK)
摘 要: 對(duì)Ti-25V-15Cr-2Al-0.2C阻燃β鈦合金的微觀組織、 拉伸性能和變形機(jī)制進(jìn)行了研究。 結(jié)果表明： (Ti, V)C和α相是β基體上的2種主要析出相； 高溫長(zhǎng)期熱暴露(540℃, 100h)后的合金晶界上形成連續(xù)的α膜， 其塑性因此急劇下降；β基體在熱暴露過(guò)程中發(fā)生微弱的短程有序化(SRO)轉(zhuǎn)變， 這在一定程度上破壞了合金的熱穩(wěn)定塑性； 該合金室溫變形以普通位錯(cuò)滑移為主要形變機(jī)制， 熱暴露后的變形結(jié)構(gòu)中出現(xiàn)少量平面滑移帶，位錯(cuò)的交滑移和攀移是合金540℃高溫變形的重要形變機(jī)制。
關(guān)鍵字: 阻燃鈦合金； 熱暴露； 微觀組織； 拉伸性能； 變形機(jī)制
of Ti-25V-15Cr-2Al-0.2C alloy
D. Rugg2, W. Voice2
（1. Laboratory of Titanium Alloys, Beijing Institute of Aeronautical Materials, Beijing 100095, China;
2. Rolls-Royce Plc, P. O. Box31, Derby DE24 8BJ, UK）
Abstract:The microstructure, tensile properties and deformation mechanisms of non-burning β titanium alloy Ti-25V-15Cr-2Al-0.2C (mass fraction, %) were investigated. The results show that, (Ti, V)C and α are two main precipitation phases in the β matrix of the alloy; after long-term exposure (540℃, 100h), the ductility of the alloy is decreased drastically, mainly due to a continuous α film formed at β grain boundaries; a low degree of short range ordering (SRO) of the β matrix occurs during long-term exposure at 540℃, which impairs the thermal stability of the alloy to a certain degree; the ordinary dislocation slip is the main mode of room plastic deformation of the alloy; a small number of planar slip bands appear in the deformation structure of the alloy after long-term exposure; dislocation cross-slip and climb are the important deformation modes of the alloy at 540℃.
Key words: non-burning titanium alloy; thermal exposure; microstructure; tensile property; deformation mechanism
