The Effect of Laser Focus Shift on the Morphology of Melt Pool and Microstructure in Selective Laser Melting AlSi10Mg

Abstract

Selective Laser Melting (SLM) enables to fabricate complex freeform geometries parts from computer models. In this paper, the effect of laser focus shift on the morphology, surface quality, grain size and texture of the SLMed AlSi10Mg was studied. Deep melt pool was found in 0 mm laser focus shift, while shallow and wide melt pool were found in-1.5 mm and +1.5 mm laser focus shift. The proportion of high angle grain boundaries in 0mm laser focus shift sample is the biggest han that in-1.5mm and +1.5mm. Height has a maximum value of 338 μm in +1.5 mm laser focus shift. The maximum Arithmetic average height is 33.5 μm in +1.5 mm laser focus shift. When the laser focus shift is 0 mm, the average grain diameter has a minimum grain diameter of 4.9 μm. {001}<100> cubic texture was found in sample fabricated by +1.5 mm laser focus shift rather than 0 mm and-1.5 mm laser focus shift.