导向套是保证液压缸活塞杆和缸筒同轴度，同时为缸口油封提供支座的关键零件，为节约 修复成本，延长液压支架导向套再服役寿命，利用激光增材再制造技术对导向套的再制造修复工艺 进行了探索。 基于数值模拟方法，建立了导向套激光增材再制造修复瞬态热分析数值模型，研究了 不同激光能量密度下导向套熔覆层上各节点处温度场及应力场的演化规律，探讨了激光能量密度 对温度场、应力场及残余应力分布的影响，通过工艺性试验优选了加工参数，采用 Cu-8Sn-3Zn 粉 末对磨损失效导向套的外圆周面进行再制造修复，并测定了熔覆层上不同节点处残余应力分布情 况。 结果表明，不同激光能量密度下，熔覆层各节点温度与应力演化都经过多次往复循环，沉积过 程结束后，逐渐趋于稳定;随着激光能量密度的增大，熔覆层温度逐渐升高，等效应力也随之增大， 当激光能量密度为 31.8 J / mm2 ，残余应力峰值出现在熔覆层终止端，为 278.54 MPa;对优选激光能 量密度 31.8 J / mm2 ，即激光功率 P = 1 000 W，扫描速度 vs = 10 mm / s 进行实验验证，发现熔覆层外 观形貌良好，无明显裂纹等缺陷;熔覆层显微组织均匀致密，无孔隙、未熔粉末的夹杂。 冷却后熔覆 层终止端残余应力峰值为 212.89 MPa，但由于残余应力受激光冲击、光粉作用机制等多因素交互 影响，导致实验测试值与数值模拟结果存在误差，但整体变化趋势一致，具有较好的工程价值与指 导意义，本研究为导向套激光增材再制造修复成形质量调控和工艺参数优化提供了参考。

The guide sleeve is a key part to ensure the concentricity of the piston rod and cylinder of the hydraulic cyl⁃ inder，and to provide the support for the oil seal at the cylinder port. In order to save the repair cost and prolong the service life of the guide sleeve of hydraulic support，this paper investigates the remanufacturing and repairing technolo⁃ gies of the guide sleeve by using laser additive remanufacturing technology. Based on the numerical simulation method，the numerical model of transient thermal analysis for the laser additive remanufacturing repair of guide sleeve is established. The evolution law of temperature field and stress field at each node of cladding layer of guide sleeve under different laser energy densities is studied. The influence of laser energy density on temperature field，stress field and residual stress distribution is discussed. The processing parameters are optimized by process test，the Cu-8Sn-3Zn powder is used to repair the outer circumference of the wear failure guide sleeve，and the residual stress distribution at different nodes of the cladding layer is measured. The results show that under different laser energy densities，the temperature and stress evolution of each node in the cladding layer go through several reciprocating cy⁃ cles，and gradually tend to be stable at the end of the deposition process. With the increase of laser energy density，the temperature of cladding layer gradually increases，and the equivalent stress also increases，when the laser energy density is 31. 8 J / mm2 . The peak value of residual stress appears at the end of cladding layer， which is 278.54 MPa. The optimal laser energy density of 31.8 J / mm2 ，namely laser power P = 1 000 W，scanning speed vs = 10 mm / s，is verified by experiments. It is found that the appearance of cladding layer is good，no obvious cracks and other defects. The microstructure of the cladding layer is uniform and dense，without holes and inclusions of unmelted powder. The peak value of residual stress at the end of cladding layer is 212.89 MPa after cooling. However，due to the interaction of laser shock，powder action mechanism and other factors，the experimental results and numerical simulation results have errors， but the overall change trend is consistent， which has a certain engineering value and guiding significance. The study provides a reference for the quality control and process parameter optimization of laser assisted remanufacturing repair of guide sleeve.