(1. 浙江工业大学 激光先进制造研究院，杭州 310023；
2. 高端激光制造装备省部共建协同创新中心，杭州 310023；
3. 浙江工业大学 机械工程学院，杭州 310023；
4. 江苏亚威机床股份有限公司，扬州 225200)
摘 要: 针对Cu材料修复需求，采用激光辅助低压冷喷涂技术(Low pressure cold spray, LPCS)在铜基体表面制备Cu涂层，研究了不同激光辐照功率对LPCS-Cu涂层微观结构及性能的影响。结果表明：LPCS-Cu涂层的孔隙率为1.23%，平均显微硬度为124.0 HV0.2，热导率为66.2 W/(m·K)，涂层/基体界面结合处存在明显缝隙。随着激光辐照功率的增大，LPCS-Cu涂层的表面趋于平整，孔隙率最低可达0.3%，平均显微硬度可达143.4 HV0.2，热导率可达170.2 W/(m·K)，且涂层与基体界面结合良好，无明显缝隙。这是由于激光辐照提高了沉积颗粒和基体的塑性变形能力，促进了沉积颗粒之间以及沉积颗粒与基体之间的相互结合，使涂层具有较好的致密性和界面结合，表现出较优的导热性能。
关键字: 冷喷涂；激光辐照；微观结构；显微硬度；导热性能
（1. Institute of Advanced Laser manufacturing, Zhejiang University of Technology, Hangzhou 310023, China;
2. Collaborative Innovation Center of High-end Laser Manufacturing Equipment, Hangzhou 310023, China;
3. College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310023, China;
4. Jiangsu Yawei Machine Tool Co., Ltd., Yangzhou 225200, China）
Abstract:In order to meet the repair needs of Cu-based materials, laser-assisted low pressure cold spray (LPCS) technology was used to prepare Cu coatings on the surface of a copper substrate in this study. The effects of different laser irradiation powers on the microstructure and performance of LPCS-Cu coatings were systematically investigated. The results show that the porosity, average micro-hardness and thermal conductivity of the LPCS-Cu coating are 1.23%, 124.0 HV0.2 and 66.2 W/(m·K), respectively. There are obvious gaps at the coating/substrate interface of the LPCS-Cu coating. As laser irradiation power increased, the surface fluctuation of LPCS-Cu coatings decrease. The porosity, average micro-hardness and thermal conductivity of the LPCS-Cu coating can be optimized to 0.3%, 143.4 HV0.2 and 170.2 W/(m·K) respectively by the assistance of laser irradiation. The interface between coating and substrate is well bonded without obvious gaps for the laser-assisted LPCS-Cu coating. Laser irradiation improves the plastic deformation ability of the deposited particles and the substrate, which is beneficial to the interfacial bonding between the deposited particles and between the deposited particles and the substrate. Therefore, the laser-assisted LPCS-Cu coating has better compactness and exhibits improved thermal conductivity performance with comparison to the counterpart without laser irradiation.
Key words: cold spray; laser irradiation; microstructure; micro-hardness; thermal conductivity
