3D morphological analysis of Fe-based metallic glass surfaces via laser powder bed fusion using a digital microscope

Surface microscopic characterization of additive manufacturing samples is necessary because of unavoidable defects in the as-printed components. However, the samples are inevitably damaged during characterization when using current methods. Herein, we propose a measurement method using a digital microscope to obtain three-dimensional (3D) morphology information related to metallic glass surfaces without damaging the samples. This study investigated the effects of processing parameters on the 3D surface morphologies of the metallic glass produced by laser powder bed fusion. The surface features of a single track, a single layer and bulk parts could be distinctly identified without damaging the samples. The results showed that the melt pool width did not increase linearly with increasing energy density, but rather had a certain upper limit. However, the height of the melt pool was strongly negatively correlated with the scanning speed. A digital microscope can allow the analysis of the macro- and micro-defects of the samples in situ. Moreover, this technique can be applied to other additive manufacturing technologies.