粉末冶金TiAl基合金排气阀的制备及性能
来源期刊:中国有色金属学报2000年第1期
论文作者:刘咏 黄伯云 贺跃辉 欧阳鸿武 郭景杰
文章页码:59 - 64
关键词:粉末冶金;TiAl基合金;柴油机;排气阀;近型成形
Key words:powder metallurgy; TiAl-based alloy; diesel exhaust valve; near net shaping
摘 要:研究了粉末冶金TiAl基合金柴油机排气阀的近型成形技术,其要点为:采用元素粉末冶金方法,以元素Ti,Al粉末为主要原料,首先在刚模中冷压成排气阀菌部;然后在真空热压炉中,通过准等静压工艺,同时实现TiAl 基合金的反应合成与近型成形;最后通过真空扩散联接工艺,使粉末冶金TiAl基合金菌部与铸态TiAl基合金杆部联接成完整的排气阀零件。通过发动机台架的初步试验表明,所制备的粉末冶金TiAl基合金排气阀表现出良好的服役性能。
Abstract: The manufacturing method and properties of P /M TiAl-based exhaust valves were investigated. The P/M TiAl-based exhaust valves were prepared through elemental powder metallurgy (EPM), i.e. elemental Ti, Al powders were used as raw material. Firstly, the mixed elemental powders were cold-pressed into a mushroomed head of the valve. Then the compacts were pseudo-HIPed, in which both the material synthesis and near net shaping were realized at one step. Finally, the P/M TiAl-based mushroomed valve heads were connected with the as-cast TiAl-based valve stems through diffusion joining technique. The primary results in diesel stand test using those valves prepared above showed that the diesel properties have met the requirements for practical application.