TiAl基合金热包覆锻造过程中温降数值分析.pdf

学兔兔 第15卷第1期 粉末冶金材料科学与工程 2010年2月 、白1．15 No．1 Materials Science and Engineering of Powder Metallurgy Feb．2010 TiAI基合金热包覆锻造过程中温降的数值分析 王 丽，刘 咏，张 伟，王 辉 (中南大学 粉末冶金国家重点实验室，长沙 410083) 摘 要：通过传热模型和数值计算，研究直径60 Inm、长100 mm的粉末冶金TiA1基合金坯料锻造时的温降规律， 对比分析裸锻和热包覆锻造坯料的温降特征。计算与实验结果表明，裸锻坯料温降高达600℃，且内部存在较大 的温度梯度，易使锻造坯失效和导致坯料组织的不均匀分布；而热包覆锻造温降仅3O℃，远低于裸锻，坯料内 部温度场分布较均匀，对锻造过程非常有利，易获得均匀、细小的锻后微观组织。粉末冶金TiA1基合金锻造过程 中的温降数值分析为TiA1基合金在热加工过程中的温降控制提供了理论依据。 关键词：粉末冶金TiA1基合金；热包覆锻造：数值计算 中图分类号：TG146．2+3 文献标识码：A 文章编号：1673．0224(2010)1—21．06 Numerical analysis 0f temperature drop of TiAI based alloys during compound canned-10rglngl -^ 』■ WANGLi，LIUYong，ZHANGWei，WANGHui (State Key Laboratory ofPowder Metallurgy,Central South University,Changsha 410083，China) Abstract：Through heat transmission model and numeric calculation，the temperature drop of powder metallugical TiA1 based alloy’S billet with size d60 minx 1 00 mm during forging was studied．The temperature drop law and level of naked forging and compound canned-forging were mainly comparatively analyzed respectively．The results from both calculation and experiment show that the great temperature drop of 600℃ and temperature gradient of naked forging make the forging ineffective and the forging compact having inhomogeneous microstructure，while the temperature drOp of compound canned-forging is only 30℃ which is far less than naked forging．and there is a uniform temperature distribution inside the billet which is rather helpful for the forged compacts to obtain uni