Multiphysics Modeling, Sensitivity Analysis, and Optical Performance Optimization for Optical Laser Head in Additive Manufacturing

Jiaping Yang,Xiling Yao,Guijun Bi,Yuxin Cai

doi:10.3390/app11020868

Abstract

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.

Highlights

Laser technology has played an important role in advanced manufacturing processes, including 3D additive manufacturing (AM), welding, cutting, and micro/nano processing, etc
A high-power laser beam passing through an optical lens could locally heat up the optical elements in the laser head
In order to mitigate these thermal effects, an optimal design of the optical laser head is desired to minimize the effect of the sources of thermal environmental changes in high-power laser material processing

Summary

Introduction

With low-cost, higher-power laser sources widely available to many manufacturing industries, there is a growing transition trend using high-power lasers in the multi-kilowatt (kW) range for material processing. The benefits of these high-power lasers are (1) scalingup processing productivity by increasing the laser spot size, the hatch spacing, and layer thickness and (2) expanding more materials such as refractory and highly reflective metals and ceramics, which usually need higher-power lasers [1]. In order to mitigate these thermal effects, an optimal design of the optical laser head is desired to minimize the effect of the sources of thermal environmental changes in high-power laser material processing

Objectives

Methods

Findings

Conclusion