| 引用本文: | 谢晓明,刘秀波,陈涛,刘志远,孟元,张世宏.激光熔覆过程数值模拟及裂纹调控研究进展[J].中国表面工程,2024,37(5):177~194 |
| XIE Xiaoming,LIU Xiubo,CHEN Tao,LIU Zhiyuan,MENG Yuan,ZHANG Shihong.Research Progress in Numerical Simulation of Laser Cladding Process and Crack Regulation[J].China Surface Engineering,2024,37(5):177~194 |
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| 摘要: |
| 激光熔覆作为一种先进的表面技术广泛应用于航空航天和军工等领域，然而激光熔覆在短时间内历经多种复杂的物化过程，其中涉及的传热传质和熔池对流行为与涂层质量密切相关，目前仅依靠试验方法难以直观准确地观测到熔覆过程的瞬态演化对涂层质量的影响，且受限于成本高和周期长等问题。而数值模拟为深入分析熔覆过程中的温度变化，应力分布和熔池流动提供了有效途径，为改善涂层质量提供了理论依据，但针对该方面的综述仍然有限。从熔覆过程中热-力-流多场动态演化出发，系统综述多物理场数值模拟方面的相关研究现状。同时针对裂纹调控问题，归纳总结导致裂纹产生的影响因素， 并概述多物理场耦合动态演化-工艺优化-裂纹调控之间的内在关联。准确的模拟结果是有效指导实践的必要条件，但目前的数值模拟研究仍难以精准反映实际熔覆情况。最后指出影响模拟准确性的难点，并对其进行展望。利用数值模拟指导激光熔覆是有效提高涂层质量的可靠手段，对该方面的研究进行系统综述可为后续相关研究和实际应用提供有益参考。 |
| 关键词: 激光熔覆 动态演化 数值模拟 工艺优化 裂纹调控 |
| DOI：10.11933/j.issn.1007-9289.20231103003 |
| 分类号:TG669；V261 |
| 基金项目:国家自然科学基金（52075559，12202507）；湖南省自然科学基金（2023JJ41051）；湖南省重点研发计划（2022GK2030）；先进金属材料绿色制备与表面技术教育部重点实验室开放基金（GFST2023KF01） |
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| Research Progress in Numerical Simulation of Laser Cladding Process and Crack Regulation |
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XIE Xiaoming1，LIU Xiubo1，CHEN Tao2，LIU Zhiyuan1，MENG Yuan1，ZHANG Shihong3
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1.Hunan Province Key Laboratory of Materials Surface / Interface Science & Technology,Central South University of Forestry & Technology, Changsha 410004 , China ；2.Wuhan Chenxi Yunfeng Technology Co., Ltd., Wuhan 430074 ；3.Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials ofMinistry of Education, Anhui University of Technology, Maanshan 243002 , China
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| Abstract: |
| Laser cladding is a three-way dynamic laser–powder–substrate interaction process in which the complex heat and mass transfer and convective behavior of the molten pool are closely related to the coating quality. Presently, it is difficult to visually and accurately observe the effect of the transient evolution of the laser cladding process on the coating quality by relying only on experimental methods, and it is limited by the high requirements of specialized equipment, high experimental costs, long cycle time, and other problems, which make it difficult to track the dynamic changes of multi-physical fields in the laser cladding process in real time. With the remarkable development of computer technology, numerical simulation provides an effective method for the in-depth analysis of the temperature change law, residual stress distribution, and melt pool flow behavior in the cladding process and provides a theoretical basis for process optimization and improvement of the coating quality. However, only a few reviews have addressed this aspect. Based on this, this paper reviews the current research status of the numerical simulation of multi-physical fields of the “temperature field–stress field–flow field” from the heat source models, thermal properties of materials, mechanical models and thermal-force coupling methods, as well as the flow behavior of the molten pool. The temperature and flow field evolution affect heat transfer, convection, and solidification in the molten pool, which directly affects the coating quality. Owing to the strong transient nature of laser cladding, stress is easily generated inside the coating, which affects its morphology, dimensions, and performance. However, current research on the numerical simulation of the laser cladding process is still limited in the accurate reflection of the actual cladding situation. In the future, it will be necessary to comprehensively consider the details of multiple physicochemical changes in the laser cladding process, such as phase transition, heat conduction, and heat convection, and build more reliable and accurate models to predict the properties of the cladding layer by considering heat source models and boundary conditions that are more compatible with laser cladding and by reducing model simplification. For the crack regulation problem, the influencing factors causing cracks are summarized. Cracks are mainly caused by residual stress exceeding the tensile strength of the material, while differences in the material properties, dilution rate, and elemental segregation also have an impact. The intrinsic correlation between multi-physics field-coupled dynamic evolution, process optimization, and crack regulation is also outlined. Numerous influencing factors lead to crack generation, and accurate simulation results are necessary to effectively guide practice. Therefore, the difficulties affecting the accuracy of the simulation are summarized, and an outlook is provided. In the future, we can improve the simulation methods, optimize the process and material systems, and combine them with nondestructive testing technology. Comprehensive simulation, experiments, monitoring, and other measures are used to establish a systematic and comprehensive crack quantitative index. Starting from the dynamic evolution level of multiscale multi-physical field coupling, realizing the integrated regulation of cracks will be the focus of future research. With continuous development and improvement at the industrial level, the realization of industrial intelligence and automation is an inevitable trend for future development, and the use of numerical simulation technology to guide the actual laser cladding process is a reliable method for effectively improving the coating quality. Therefore, a systematic review of the intrinsic connection between the dynamic evolution of multi-physics fields in laser cladding and crack regulation is necessary to provide references for subsequent research or practical work on numerical simulation and crack regulation of the laser cladding process. |
| Key words: laser cladding dynamic evolution numerical simulation process optimization crack regulation |
