(1.中南工業(yè)大學(xué)粉冶所，長沙410083；
2.中科院北京電鏡室，北京100080)
摘 要: 研究了熱加工和熱處理對TiAl基合金顯微組織的影響。試驗(yàn)發(fā)現(xiàn)，三向壓應(yīng)力能顯著地提高合金的熱變形塑性，實(shí)現(xiàn)無破損大應(yīng)變速率熱變形。分析表明，常規(guī)熱變形工藝下試樣中仍存在粗大層片狀晶團(tuán)，且不能由隨后熱處理消除，而復(fù)合熱機(jī)械處理新工藝能在整個試樣上得到細(xì)小、均勻的顯微組織。
關(guān)鍵字: TiAl基合金 熱變形 顯微組織
（Powder Metallurgy Research Institute，Central South University of Technology，Changsha 410083）
Abstract:The effects of hot working and heat treatment on microstructure of TiAI-based alloys were investi-gated. The test results indicated that three-dimension stress state could promote hot deforming plasticity of TiAl based alloys efficiently, and large press ratio forging of samples without surface crack under a high strain rate could be obtained. The coarse lamellar grains were retained in samples which experienced normal hot deformation and could not be removed by following heat treatment，while homogeneous and refined microstructure could be ob-tamed throughout the whole samples under a new process of multi-thermal-mechanical treatment.
Key words: TiAl-based alloy hot deformation microstructure
