激光熔覆中工艺参数对形成层几何特征及硬度影响分析

摘要

激光熔覆技术的实质是合金粉末快速熔化和凝固的过程,其形成层的形状和性能与工艺参数密切相关.为了了解工艺参数对激光熔覆形成层几何特征及硬度的影响规律,根据正交试验设计方法设计研究了工艺参数(激光功率、扫描速率、送粉速率)对单道单层熔覆层几何特征(熔覆层高度、宽度与熔池深度)与硬度影响的试验,根据试验结果归纳了工艺参数对单道单层熔覆层几何特征与硬度的影响规律,解释了造成这些影响的原因,试验表明激光功率是影响熔覆层几何特征的最显著因素.此外,使用了一个激光熔覆层的几何特征数学模型对照验证了试验结果.%Laser cladding is the process that alloy powders get melted and solidified rapidly.The shape and properties of forming layer are closely related to process parameters.To study the effect rules of laser cladding process parameters on forming layer's geometric characteristics and hardness, an orthogonal experiment is designed to explore the influence of laser power,scanning speed and powder feed rate on single-line single-level cladding layer's geometric characteristics,including the height and width of the cladding layer,the depth of the melting pool and the hardness.The effect patterns of those process parameters on single-line single-level cladding layer' s geometric characteristics and hardness are concluded and their underlying reasons are explained.The experiment results show that laser power is the parameter with the most significant effect on the cladding layer's geometric characteristics.A mathematical model of laser cladding layer's geometric characteristics is used to validate the results of the experiments.