基于有限差分的奥氏体钢焊接凝固裂纹计算分析  

CALCULATION AND ANALYSIS OF WELDING SOLIDIFICATION CRACK OF AUSTENITIC STEEL BASED ON FINITE DIFFERENCE

作　　者：蔡小莉 Cai Xiaoli(Chongqing Chemical Industry Vocational College, Chongqing 400020, China)

机构地区：[1]重庆化工职业学院,重庆400020

出　　处：《计算机应用与软件》2019年第2期284-288,328,共6页Computer Applications and Software

摘　　要：提出奥氏体不锈钢焊接凝固裂纹预测的计算策略,建立阶梯模型,并分析其在焊接凝固裂纹预测过程中的数值稳定性和收敛性。研究发现,阶梯模型的二维偏析计算接近凝固裂纹的物理行为,且具有最佳的数值稳定性和收敛性。对阶梯模型的算法进一步优化,解决焊接凝固过程中凝固时间、温度和枝晶生长模型引起的计算误差问题。结合横向可变拘束裂纹实验的裂纹敏感性评估结果,验证所建立的优化阶梯模型用于焊接凝固裂纹敏感性预测的有效性,其误差为30%左右。In this paper, we proposed a calculation strategy for predicting solidification cracks of austenitic stainless steel welding, and established a stair model. We analyzed the numerical stability and convergence of this model in the process of predicting solidification cracks. The two-dimensional segregation calculation of stair model was close to the physical behavior of solidification cracks, and has the best numerical stability and convergence. The algorithm of stair model was further optimized to solve the calculation error caused by solidification time, temperature and dendrite growth model in solidification process. Combining with the results of crack sensitivity evaluation of trans-varestraint test, the validity of the optimized stair model for predicting weld solidification cracks sensitivity was verified, and the error is about 30%.

关 键 词：凝固裂纹敏感性 阶梯模型 横向可变拘束 

分 类 号：TP3[自动化与计算机技术—计算机科学与技术]