Optical laser head is a key component used to shape the laser beam and to deliver higher power laser irradiation onto workpieces for material processing. A focused laser beam size and optical intensity need to be controlled to avoid decreasing beam quality and loss of intensity in laser material processing. This paper reports the multiphysics modeling of an in-house developed laser head for laser-aided additive manufacturing (LAAM) applications. The design of computer experiments (DoCE) combined with the response surface model was used as an efficient design approach to optimize the optical performance of a high power LAAM head. A coupled structural-thermal-optical-performance (STOP) model was developed to evaluate the influence of thermal effects on the optical performance. A number of experiments with different laser powers, laser beam focal plane positions, and environmental settings were designed and simulated using the STOP model for sensitivity analysis. The response models of the optical performance were constructed using DoCE and regression analysis. Based on the response models, optimal design settings were predicted and validated with the simulations. The results show that the proposed design approach is effective in obtaining optimal solutions for optical performance of the laser head in LAAM.

中文翻译：

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增材制造中光学激光头的多物理场建模，灵敏度分析和光学性能优化

光学激光头是用于成形激光束并将高功率激光辐照到工件上进行材料加工的关键组件。需要控制聚焦的激光束大小和光强度，以避免在激光材料加工中光束质量下降和强度损失。本文报告了针对激光辅助增材制造（LAAM）应用的内部开发激光头的多物理场建模。计算机实验（DoCE）的设计与响应面模型相结合，被用作优化高功率LAAM头的光学性能的有效设计方法。建立了结构热光性能耦合（STOP）模型以评估热效应对光学性能的影响。许多使用不同激光功率的实验 使用STOP模型设计和模拟激光束焦平面位置和环境设置，以进行灵敏度分析。使用DoCE和回归分析构建了光学性能的响应模型。基于响应模型，可以预测最佳设计设置并通过仿真进行验证。结果表明，所提出的设计方法可有效地获得LAAM中激光头光学性能的最佳解决方案。