感应加热熔丝复合激光焊接厚板中热源及熔丝耦合机制研究

项目名称： 感应加热熔丝复合激光焊接厚板中热源及熔丝耦合机制研究

项目编号： No.51505145

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 机械、仪表工业

项目作者： 李时春

作者单位： 湖南科技大学

项目金额： 21万元

中文摘要： 高功率激光焊接厚板技术是大型装备结构件焊接制造的发展新方向。然而，激光焊接厚板时存在焊接稳定性差、极易产生焊接缺陷、焊缝成型不稳定、优化焊接参数窗口窄的瓶颈问题。本项目提出感应加热熔丝复合高功率光纤激光焊接厚板的新工艺，并对其相关机理及工艺开展研究。项目通过建立包含感应加热、熔丝过渡、激光小孔焊接过程中的传热和复合流场的多物理场耦合数值计算理论模型，研究多热源相互耦合关系和多热源能量利用比例对焊接结果的影响，揭示热源耦合机制、获得能量分配优化方案、形成低能耗焊接的相关理论；研究熔丝与熔池间的耦合行为、熔丝-熔池-焊接小孔间的相互作用关系，揭示复合焊接熔丝对熔池、焊接小孔及焊接稳定性的影响规律，阐明熔丝对厚板焊接熔池稳定性的调控机制，揭示熔丝对抑制焊接缺陷的作用机制。项目成果为实现厚板的高效、低能耗、高质量、高稳定性焊接提供理论和试验基础。项目丰富和发展了感应加热、激光焊接和复合焊接技术。

中文关键词： 激光复合焊接；感应加热；熔丝；复合热源；耦合机制

英文摘要： High power laser welding of thick plate is the new trend of larger equipment structure welding manufacturing. However, the technology of laser welding of thick plate has bottleneck problems, such as poor welding stability, easily generated welding defects, changeful welding appearance, and narrow welding process window. In the present project, the inductive heated molten filler / laser hybrid welding of thick plate has been proposed, and the related mechanisms and process are studied. The multiple-physical coupling model consisting of heat transfer and integrated flow field is contributed, which includes the process of inductive heating, molten filler transition, and laser keyhole welding. Based on the model, the coupling relationship between multiple heat sources and the influences of energy utilization factors of heat sources on welding result are investigated. The coupling mechanisms of heat sources are revealed, the optimization scheme of energy distribution is obtained, and the correlation theory of low-energy welding is summarized. The coupling behavior between molten filler and molten pool and the interactive relationships between molten filler, molten pool and welding keyhole are researched. The influence rules of hybrid welding molten filler on molten pool, welding keyhole and welding stability are revealed. The regulating mechanisms of molten filler to molten pool stability during thick plate welding are illuminated. And, the suppression mechanisms of molten filler to welding defects are revealed. The project results provide the theoretical and experimental foundations to realize high efficiency, low energy consumption, high quality, and high stability of thick plate welding. The project will enrich and develop the inductive heating, laser welding and hybrid welding technologies.

英文关键词： laser hybrid welding;inductive heating;molten filler;hybrid heat source;coupling mechanism