烟气轮机涡轮盘锻造开裂原因分析
Analysis on Crack of Turbine Disk During Forging
袁国栋1, 杨运民1,2, 石 静1, 王艳蕾1
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作者单位:1.重庆大学机械传动国家重点实验室, 重庆 400044; 2.中国二重集团公司, 四川 德阳 618013
中文关键字:数值模拟; Waspaloy合金; 涡轮盘; 开裂分析; 断裂准则
英文关键字:numerical simulation; Waspaloy alloy; turbine disk; crack analysis; fracture criterion
中文摘要:在TMTS热模拟机上采用等温压缩试验研究Waspaloy合金高温压缩变形行为,获得合金在温度为1000~1160℃、应变率为0.01~1s-1条件下的真应力-应变曲线,通过单向拉伸试验获得了该合金在温度为850~1250 ℃、应变率为0.01~1s-1条件下的伸长率-温度曲线。根据试验结果,应用Normalized Cockcroft & Lat ham韧性断裂准则,结合数值模拟技术对烟气轮机涡轮盘锻造开裂原因进行了分析。分析结果表明:模具和坯料的初锻温度过低是引起锻件开裂的重要原因。根据锻造开裂原因的分析结果,提出了避免开裂的工艺方案,并对新方案进行了数值模拟,后续的模拟结果证明,新方案可以有效避免锻造裂纹的产生。
英文摘要:The hot deformation behavior of Waspaloy nickel-based alloy were investigated by hot compression tests with TMTS simulated machine. The true stress-true strain curves under the temperature of 1000 ~ 1160 ℃ and strain rate of 0.01s-1~1s-1 were obtained. An analysis on the crack of turbine disk during forging was presented by numerical simulation technology based on the Normalized Cockcroft & Latham ductile fracture criterion, the turbine disk was made of Waspaloy alloy. The results show that the cracks in the turbine disk may be caused by the lower initial temperature of the turbine disk and the dies. According to the conclusion, an impropved forging process is suggested. The numerical simulation show that the improved forging process can avoid the crack.