揭示热传导环境因素对熔覆成形质量的影响规律, 是指导高价值零件的高质量精确修复的前提。采用全因素试验法研究基体预热温度、基体接触导热系数、基体规格3个热传导因素对熔覆层宏观形貌、稀释率以及内部组织缺陷的影响规律。研究表明, 熔覆层稀释率随着基体预热温度增加及导热系数减小而增大, 基体规格影响不显著; 当基体预热300 ℃、导热材料为石棉、基体规格为40 mm×10 mm×5 mm时熔覆层表面光滑平整、内部无明显气泡裂纹, 组织生长均匀。研究结果为实现外部环境对熔覆涂层成形质量的控制及预测提供理论依据。

The premise of guiding the precise high-quality repair of high-value parts is to reveal the influence of heat conduction environmental factors on the forming quality of laser cladding. An all-factor experimental method was adopted to study the effects of three heat conduction factors on the macro morphology, dilution ratio, and internal tissue defects of the cladding layer. These three factors include the substrate preheating temperature, substrate thermal conductivity and size of the substrate. The research shows that the dilute ratio of the cladding layer increases with the rising of the preheating temperature and the decreasing of the thermal conductivity. However, the substrate size has no significant influence. With the preheating temperature of the substrate at 300 ℃, the asbestos as heat conduction material and the size of the substrate is 40 mm×10 mm×5 mm, the cladding layer has smooth surfaces with no obvious bubble cracks inside, and the tissue growth is homogeneous. The research results provide a theoretical basis for realizing the control and prediction of the forming quality of cladding coating by the external environment.