基于热处理数值分析的大型支承辊锻后热处理工艺优化  

Optimization on heat treatment process after forging of large supporting roller based on numerical analysis of heat treatment

作　　者：林洪[1] 刘利[1] 

机构地区：[1]重庆工业职业技术学院机械工程学院,重庆401147

出　　处：《锻压技术》2015年第12期141-144,共4页Forging & Stamping Technology

摘　　要：对大型轧机支承辊进行断裂失效分析,发现心部偏析和组织不均匀以及由此造成的残余应力是支承辊断裂的主要原因。利用Deform有限元软件对该支承辊锻后热处理工艺进行数值模拟,分析原锻后热处理工艺中支承辊的温度场、应力场和组织场,发现支承辊心部热处理过程中奥氏体化保温时间少、空冷后入炉温度低,正火后残余应力过大。提出降低加热速度为10℃·h^(-1),提高完全奥氏体保温温度为930℃和延长保温时间至30 h,提高入炉温度的优化锻后热处理工艺。研究结果表明:采用优化工艺可以解决支承辊心部完全奥氏体化保温时间不足,并降低了热处理残余应力和断裂风险。For the fracture failure analysis on the supporting roller of a large mill, it was found that the center segregation, the inhomoge- neous microstructure and the resuhing residual stress were the main reasons of supporting roller fracture. The heat treatment process after forging of the supporting roller was simulated by Deform. It was discussed the supporting roller＇s temperature field, stress field and microstructure field under the original heat treatment after forging. It was found that the austenizing time in the middle of supporting roller was less, the temperature was lower after air cooling, and the residual stress was larger after normalizing. The corresponding optimization heat treatment process was put forward, namely, decreasing heat velocity to 10 ℃ .h- 1 , increasing austenizing temperature and time to 930℃ and 30h respectively, increasing temperature after air cooling. The result shows that the optimization process can resolve the lack of austenizing time in the middle of the supporting roller, and reduce the residual stress of heat treatment and fracture risk.

关 键 词：热处理数值分析 大型支承辊 锻后热处理 换热系数 

分 类 号：TG333[金属学及工艺—金属压力加工] TG316