Comprehensive assessment of spatter material generated during selective laser melting of stainless steel

Laser-powder interaction and meltpool dynamics govern the physics behind the selective laser melting process. Spattering is an unavoidable phenomenon taking place during the process which is known to influence the integrity of the interaction between the incident laser beam and change the powder bed characteristics. This can consequently have a negative effect on final part integrity and quality of recycled powder. Hence, it is crucial to assess the characteristics of spatter particles to avoid the printing of defective parts. This work reports a detailed characterisation of spatter matter generated during selective laser melting of stainless steel. To better assess the characteristics of the spatter, the spattered material was benchmarked against the virgin powder. The results show no microstructural differences. However, the spatter morphological, chemical, optical and physical properties assessed in this work differ from the virgin powder. The results presented in this work are of significant contribution to the powder bed fusion field of additive manufacturing as it provides a unique insight to the characteristics of spatter matter generated from the processing of 316L stainless steel powde