大型锻件凹型角度砧拔长工艺  

Stretching of heavy forgings with a concave anvil

作　　者：刘鑫[1] 钟约先[1] 马庆贤[1] 袁朝龙[1] 

机构地区：[1]清华大学机械工程系,先进成形制造教育部重点实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2010年第7期965-969,共5页Journal of Tsinghua University(Science and Technology)

基　　金：“十一五”国家科技支撑计划项目(2007BAF02B07,2007BAF02B01);国家自然科学基金项目(50705048);教育部博士点基金项目(20070003080)

摘　　要：随着大型核电低压转子锻件尺寸和重量的增加,低压转子锻件锻透成为锻造过程的突出难题。该文通过改变砧形,采用凹型角度砧拔长的工艺来增加心部压实效果,并通过数值模拟和物理模拟相结合的方法对其应力应变的分布进行了研究。模拟结果表明:采用凹型角度砧拔长,增加了心部变形效果,改善了心部的应力状态,有利于心部压实和缺陷锻合;采用6°的凹型角度砧比平砧可以得到更好的应力应变状态。建议在大型锻件主拔长的前几趟次采用凹型角度砧拔长工艺。The low-pressure rotor in a nuclear power plant turbine is quite large and heavy,so forgings are difficult.A forging process using FM with a concave anvil（FMCcA） in the stretching processing was developed to improve the internal quality of heavy forgings.The stress and strain distributions in the forging were investigated using a combination of modeling and numerical simulations.The results show that using the concave anvil in the stretching processing increases the deformation at the center of the billet and improves the stress state in the center region.The billet had better stress and strain distributions using a 6°concave anvil than with a common flat anvil in stretching processing.The results suggest that the FMCcA should be used in the first or second stretching steps.

关 键 词：大型锻件 数值模拟 应力 锻造工艺 

分 类 号：TG316[金属学及工艺—金属压力加工]