Laser beam Powder Bed Fusion (PBF-LB) is an increasingly attractive technology due to its capability of manufacturing complex and customised metal parts. However, the build cycle time and resulting residual stress profiles are limiting a wider uptake of PBF-LB manufacturing. The incorporation of additional laser beams in a single build chamber, i.e. multi-laser beam Powder Bed Fusion (PBF-MLB) technology, has been proposed as the next generation of PBF-LB technology. A series of computational process simulations of PBF-MLB was carried out using a 3D coupled thermomechanical model to investigate optimum multi-laser scanning strategies. The influences of twelve different scanning strategies on temperature, the final residual stresses, the z- (build) direction deflections by dual Gaussian profile laser beams PBF-MLB were investigated. It was found that the 90° layer rotation is necessary to reduce the residual stress, and a ‘dual-laser following but time-delayed’ scanning strategy had the lowest final residual stress. Another scanning strategy (45° rotation approaching beam scanning) resulted in the lowest z-direction deflection for the dual laser beams PBF-MLB manufacturing. These findings provide insight and application of PBF-MLB finite element process simulation in improving industrial additive manufacturing of metal components.

激光束粉末床融合（PBF-LB）由于具有制造复杂的和定制的金属零件的能力而成为一种越来越有吸引力的技术。但是，构建周期时间和所产生的残余应力曲线限制了PBF-LB制造的广泛应用。已提出将附加激光束合并到单个构建腔室中，即多激光束粉末床融合（PBF-MLB）技术作为下一代PBF-LB技术。使用3D耦合热力学模型对PBF-MLB进行了一系列计算过程仿真，以研究最佳的多激光扫描策略。研究了十二种不同扫描策略对温度，最终残余应力，双高斯轮廓激光束PBF-MLB的z-（方向）变形的影响。已经发现，旋转90°层对于减小残余应力是必要的，并且“双激光跟随但延时的”扫描策略具有最低的最终残余应力。另一种扫描策略（接近光束扫描45°旋转）使双激光束PBF-MLB制造的Z方向偏转最小。这些发现为PBF-MLB有限元过程仿真在改善金属零件的工业增材制造方面提供了见识和应用。