Comprehension of overhanging structure distortion via selective laser melting based on theory of constraining force induced distortion

Overhanging structure is common seen in selective laser melting for it is used to fabricate complex structure. The distortion of overhanging structure is hard to be avoid. The physical cause of distortion has been relatively unknown. In this paper, a physical model was established for illustrating the cause of distortion of overhanging structure via selective laser melting, based on a proposed theory of constraining force induced distortion. The distortion of overhanging structure with different angles, as well as with different scanning patterns, were studied based on experimental results. It can be concluded that the different scanning paths can lead to different constraining force directions, thus causing different distortion. Besides, suitable structure design is beneficial for decreasing distortion of overhanging structure.