钒元素对预合金粉末在球磨阶段退火显微组织的影响机理

The Influence Mechanism of Vanadium Element on the Microstructure of Pre-alloyed Powder Ball Milling Process and Annealing

为探明钒元素对预合金粉性能的影响机制,采用高能球磨法SPS制备Ti_(2)AINb预合金,按照是否掺入钒元素制备两类样品,对比分析纤维组织及相结构。结果表明:未经200℃、2 h退火球磨后Ti_(2)Al Nb预合金粉明显长大,可对其SPS热压烧结,无氧化物相;向Ti_(2)Al Nb合金掺入钒元素后,提高a_(2)相与O相含量,影响合金结晶方式,a_(2)相含量在钒元素原子分数为2%时最高;钒元素原子分数提高至3%,合金发展为层片网篮组织,分布均匀,形态以细小状为主,组织边界随着钒元素含量提高变得愈发圆润,在Ti_(2)Al Nb合金制备时掺入适量钒元素,能够改善合金显微组织和相结构,提升合金力学性能。

In order to investigate the influence mechanism of vanadium element on the properties of pre-alloy powder,Ti_(2Al) Nb pre alloy was prepared by high-energy ball milling SPS method.Two types of samples were prepared according to whether vanadium element was added,and the fiber structure and phase structure were compared and analyzed.The results showed that the Ti_(2Al) Nb pre alloy powder significantly grew after annealing at 200℃for 2 hours,and could be sintered by SPS hot pressing without oxide phase.After adding vanadium to Ti_(2Al) Nb alloy,the content of phase O is increased,which affects the crystallization mode of the alloy.The phase content is highest when the vanadium content is 2%.The vanadium content is increased to 3%,and the alloy develops into a layered mesh basket structure with uniform distribution and mainly fine morphology.The boundary of the organization becomes more rounded with the increase of vanadium content.Adding an appropriate amount of vanadium element during the preparation of Ti_(2Al) Nb alloy can improve the microstructure and phase structure of the alloy,and enhance its mechanical properties.