机械工程材料
MATERIALS FOR MECHAMICAL ENGIMEERIVG DOI:10.11973/jxgccl201512016
2015年12月第39卷第12期Vol.39No,12 Dec.2015
Inconel 625镍基合金管道焊接残余应力的数值模拟
姬丽森，凌泽民，何建
（重庆大学材料科学与工程学院，重庆400044）
摘要：以Inconel625镍基合金管道的焊接接头为研究对象，建立了热-力学耦合的三维有限元模型，采用ANSYS软件对该合金管道环焊缝对称的残余应力进行了数值模拟，分析了管道外表面轴向和环向残余应力分布，并进行了试验验证：此外，还分析了预热温度对管道残余应力的影响。结果表明：该合金管道焊后外表面轴向与环向残余应力的模拟结果与试验结果在数值和分布趋势上均比较吻合，证明了模型的准确性；在焊缝及近焊缝区的管道外表面形成了轴向压应力和环向拉应力，随着距焊缝中心距离的增加，轴向压应力逐渐变为拉应力，而环向拉应力逐渐转变为压
应力，并最终趋向于0；随着预热温度的升高，管道外表面轴向和环向残余应力均降低。关键调：Inconel625镍基合金：管道；预热；残余应力；数值模拟
中图分类号：TG404
文献标志码：A
文章编号：1000-3738(2015)12-0067-04
Numerical SimulationofWeldingResidualStress
inInconel625Nickel-basedAlloyTube
JI Li-sen,LING Ze-min,HE Jian
(School of Material Science and Engineering, Chongqing University, Chongqing 400044, China)
Abstract: Based on the butt joint of Inconel 625 nickel-based alloy tube, the three-dimensional thermal and mechanical finite element model was established. The ANSYS software was used to simulate the residual stress of the nickel-based alloy tube after girth welded by the symmetry welding method, and the simulated distribution of axial and hoop residual stress on outer surface of the tube were analyzed and verified by experiment. In addition, the effect of the preheating temperatures on the residual stresses was investigated. The results show that the axial and hoop residual stress distribution on outer surface of the tube obtained by simulation coincided well with the experimental results, indicating the aceuracy of the simulation model. The axial residual compressive stresses and hoop residual tensile stresses formed on outer surface of the weld and near weld zone. With the increase of the distance from the weld center line, the axial compressive stress gradually turned to tensile stress and hoop tensile stress to compressive stress, and then tended to zero. The axial and hoop residual stresses both decreased with the increase of the preheating temperature.
Key words: Inconel 625 nickel-based alloy; tube: preheating; residual stress; numerical simulation
0引言
Inconel625镍基合金具有较高的强度和塑性，
优异的疲劳和热疲劳强度、氧化抗力、耐腐蚀性能，优良的焊接性，广泛应用于航空航天、船舶、核能和石油化工等领域[1-S}]。该合金制造的管道在应用时
收稿日期：2014-11-08；修订日期：2015-10-21
作者简介：姬丽森（1990一），女，河南焦作人，硕士研究生，导师：凌泽民副教授
需要进行焊接，而焊接是一个局部不均勾加热和冷却的过程，易在焊接接头处产生残余应力，影响到管道的强度、刚度和承载能力，并诱发应力腐蚀3]。因此，焊接残余应力受到了人们的产泛关注
有限元模拟是伴随着计算机技术和数值分析方法发展而发展起来的结构分析方法，被广泛地应用于焊接热传导分析、应力和变形分析、焊接结构断裂分析等方面。通过有限元软件可对焊接残余应力进行精确模拟，从而优化焊接结构设计以及工艺参数，
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