Elimination of misrun and gas hole defects of investment casting TiAl alloy turbocharger based on numerical simulation and experimental study  

作　　者：Jun Zhao Zhi-yong Zhang Shi-bing Liu Kun Shi Chun-ling Bao Zhao-sheng Ning Ping Yan Lei Wang Yan-chun Lou 

机构地区：[1]State Key Laboratory of Light Alloy Casting Technology for High-end Equipment,Shenyang 110022,China [2]Shenyang Research Institute of Foundry Co.,Ltd.,Shenyang 110022,China [3]Northeastern University,Shenyang 110189,China

出　　处：《China Foundry》2020年第1期29-34,共6页中国铸造（英文版）

基　　金：financially supported by the Liaoning Natural Science Foundation ( Grant No.20170540888);the Liaoning Science and Technology Project (Grant No.2017221006)

摘　　要：Casting technology of thin-wall TiAl alloy turbochargers was studied by investment casting and numerical simulation.Misruns and gas holes were the main defects observed in preliminary work due to the poor fluidity of alloy,and to gas entrapment.In order to eliminate these defects,cast parameters,such as centrifugal rotation rate and mould preheating temperature,were optimized by numerical simulation,meanwhile,the structure of the shell mould was optimized to improve the filling capacity of TiAl alloy.Pouring experiments were carried out by vacuum induction melting furnace equipped with a water-cooled copper crucible based on the above optimization.The quality of the TiAl alloy casting was analyzed by fluorescent penetrant inspection and X-ray detection.The results show that a centrifugal rotation rate of 200 rpm,mould preheating temperature of 600°C,shell preparation through organic fiber addition can dramatically improve the mould filling capacity,and integrated turbochargers were finally prepared.Casting technology of thin-wall Ti Al alloy turbochargers was studied by investment casting and numerical simulation. Misruns and gas holes were the main defects observed in preliminary work due to the poor fluidity of alloy, and to gas entrapment. In order to eliminate these defects, cast parameters, such as centrifugal rotation rate and mould preheating temperature, were optimized by numerical simulation, meanwhile, the structure of the shell mould was optimized to improve the filling capacity of Ti Al alloy. Pouring experiments were carried out by vacuum induction melting furnace equipped with a water-cooled copper crucible based on the above optimization. The quality of the Ti Al alloy casting was analyzed by fluorescent penetrant inspection and X-ray detection. The results show that a centrifugal rotation rate of 200 rpm, mould preheating temperature of 600 °C, shell preparation through organic fiber addition can dramatically improve the mould filling capacity, and integrated turbochargers were finally prepared.

关 键 词：titanium aluminide cast defects TURBOCHARGER investment casting 

分 类 号：TG146.23[一般工业技术—材料科学与工程]