焊接熔池流体动力学行为的数值模拟和实验研究
发布时间：2018-07-21 16:04
【摘要】：在对激光焊接过程中匙孔壁面受力平衡状态和金属蒸发情况研究基础上,建立了随匙孔深度和形貌变化的自适应热源模型。采用Particle Level Set方法来跟踪熔池内的匙孔自由表面,对2A12合金和30CrMnSiA钢激光深熔焊过程进行了数值模拟,分析了材料性能和侧吹气体对熔池-匙孔内的温度场、流场和匙孔动态演化过程的影响。研究结果表明,相同工艺参数下热导率较小的材料,更容易形成深而窄的焊缝形貌。而侧吹气流气体的加入不仅能够改善熔池内流体的流动状态,而且能够显著地抑制焊缝中气孔产生。在此基础上,利用熔池动态监测技术对激光焊接中熔池的动态行为进行了实验观测,得到了熔池内匙孔颈缩、塌陷、闭合以及气泡的形成过程,进一步验证了模拟结果的合理性。在对不同侧吹气流下焊缝气孔检测和模拟结果分析的基础上,提出了增强焊接稳定性和降低气孔敏感性的新思路。
[Abstract]:Based on the study of the stress balance state and metal evaporation of the keyhole wall during laser welding, an adaptive heat source model with the variation of the depth and morphology of the keyhole was established. The Particle level set method is used to track the free surface of keyhole in the molten pool. The process of laser deep fusion welding of 2A12 alloy and 30CrMnSiA steel is numerically simulated. The material properties and the temperature field of side blowing gas in the weld pool and keyhole are analyzed. The influence of the flow field and the dynamic evolution of the keyhole. The results show that it is easier to form deep and narrow weld morphology of materials with lower thermal conductivity under the same process parameters. The addition of side blowing gas can not only improve the flow state of the fluid in the molten pool, but also significantly inhibit the formation of pores in the weld. On this basis, the dynamic behavior of molten pool in laser welding is observed by using the technology of dynamic monitoring of molten pool. The process of necking, collapsing, closing and bubble formation of keyhole in molten pool is obtained. The rationality of the simulation results is further verified. Based on the analysis of gas hole detection and simulation results of weld under different side blowing flow, a new way of improving welding stability and reducing porosity sensitivity is put forward.
【作者单位】： 中国工程物理研究院总体工程研究所;
【基金】：国家自然科学基金(11372295) 中国工程物理研究院重大基金(2013A0203008);中国工程物理研究院重点学科项目“计算固体力学”资助
【分类号】：TG456.7
，
本文编号：2136050
[Abstract]:Based on the study of the stress balance state and metal evaporation of the keyhole wall during laser welding, an adaptive heat source model with the variation of the depth and morphology of the keyhole was established. The Particle level set method is used to track the free surface of keyhole in the molten pool. The process of laser deep fusion welding of 2A12 alloy and 30CrMnSiA steel is numerically simulated. The material properties and the temperature field of side blowing gas in the weld pool and keyhole are analyzed. The influence of the flow field and the dynamic evolution of the keyhole. The results show that it is easier to form deep and narrow weld morphology of materials with lower thermal conductivity under the same process parameters. The addition of side blowing gas can not only improve the flow state of the fluid in the molten pool, but also significantly inhibit the formation of pores in the weld. On this basis, the dynamic behavior of molten pool in laser welding is observed by using the technology of dynamic monitoring of molten pool. The process of necking, collapsing, closing and bubble formation of keyhole in molten pool is obtained. The rationality of the simulation results is further verified. Based on the analysis of gas hole detection and simulation results of weld under different side blowing flow, a new way of improving welding stability and reducing porosity sensitivity is put forward.
【作者单位】： 中国工程物理研究院总体工程研究所;
【基金】：国家自然科学基金(11372295) 中国工程物理研究院重大基金(2013A0203008);中国工程物理研究院重点学科项目“计算固体力学”资助
【分类号】：TG456.7
，
本文编号：2136050
本文链接：https://www.wllwen.com/kejilunwen/jiagonggongyi/2136050.html
