Multiple material laser powder bed fusion (MMLPBF) is a recently developed technology that broadens the application range of additive manufacturing. Experiencing dissimilar materials interactions, the physical phenomena in the MMLPBF process are more complex. In this study, a computation fluid dynamic model in the mesoscale for simulating single-track MMLPBF melt pool behavior is developed. The characteristics of melting IN718/Cu10Sn powder beds were investigated. It is shown that in melting a mixed IN718/Cu10Sn powder bed, the temperature of the melt pool decreases with increasing Cu10Sn fraction, owing to the difference in the thermal–physical properties of dissimilar metals, particularly the melting points, laser beam absorptivity and thermal conductivity. A braze zone is formed on the edge of a solidified track on the powder bed with mixed dissimilar powders having melted Cu10Sn and un-melted or partially melted In718, which results in fluctuations in the track dimensions. For unmixed dissimilar powder beds, an asymmetrical melt pool and solidified track are formed if the laser spot overlaps the interface of the dissimilar powders. The effect of hatch spacing in multiple track melting on a mixed dissimilar powder bed is also studied. It indicates that owing to the significant fluctuation in the track dimensions, the hatch spacing should be adjusted adaptively and should be less than the width of the melted zone to avoid insufficient intertrack fusion.

多材料激光粉末床熔合（MMLPBF）是一项最新开发的技术，可拓宽增材制造的应用范围。经历不同的材料相互作用，MMLPBF过程中的物理现象更加复杂。在这项研究中，中尺度的计算流体动力学模型用于模拟单轨MMLPBF熔池行为。研究了熔化IN718 / Cu10Sn粉末床的特性。结果表明，在熔化混合的IN718 / Cu10Sn粉末床中，熔池的温度随着Cu10Sn分数的增加而降低，这是由于异种金属的热物理性质（尤其是熔点，激光束吸收率和热能）不同所致。电导率。在粉末床上固化轨道的边缘上形成钎焊区，其中混合的异种粉末具有熔融的Cu10Sn和未熔融或部分熔融的In718，这会导致轨道尺寸波动。对于未混合的异种粉末床，如果激光光斑与异种粉末的界面重叠，则会形成不对称的熔池和凝固轨迹。还研究了混合异种粉末床上多轨熔化中的舱口间距的影响。它表明，由于轨道尺寸的明显波动，舱口间距应进行自适应调整，并应小于融化区的宽度，以避免轨道间融合不足。对于未混合的异种粉末床，如果激光光斑与异种粉末的界面重叠，则会形成不对称的熔池和凝固轨迹。还研究了混合异种粉末床上多轨熔化中的舱口间距的影响。它表明，由于轨道尺寸的明显波动，舱口间距应进行自适应调整，并应小于融化区的宽度，以避免轨道间融合不足。对于未混合的异种粉末床，如果激光光斑与异种粉末的界面重叠，则会形成不对称的熔池和凝固轨迹。还研究了混合异种粉末床上多轨熔化中的舱口间距的影响。它表明，由于轨道尺寸的明显波动，舱口间距应进行自适应调整，并应小于融化区的宽度，以避免轨道间融合不足。