作　　者： ; ; ; ;

机构地区： 中南大学材料科学与工程学院粉末冶金国家重点实验室

出　　处： 《粉末冶金材料科学与工程》 2010年第1期21-26,共6页

摘　　要： 通过传热模型和数值计算,研究直径60mm、长100mm的粉末冶金TiAl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30℃,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TiAl基合金锻造过程中的温降数值分析为TiAl基合金在热加工过程中的温降控制提供了理论依据。 Through heat transmission model and numeric calculation,the temperature drop of powder metallugical TiAl based alloy＇s billet with size d60 mm×100 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 uniform and fine microstructure. This kind of numerical analysis for temperature drop of powder metallurgical TiAl-based alloy supplies a theoretical foundation for TiAl alloy to controlling temperature drop in practical hot working.

关 键 词： 粉末冶金 基合金 热包覆锻造 数值计算

领　　域： [金属学及工艺] [一般工业技术] [金属学及工艺]