Effect of linear energy density on pores of 316L stainless steel by selective laser melting

The defects of forming parts with different process parameters (laser power, scanning speed and scanning distance) were studied by microscope, including air bubble, pore, micro-crack and macro-crack. The micro-structure and composition of the defects were studied by means of SEM and EDS. The results showed that the pore mainly included circular air pore, irregular process pore and oxide inclusion. Linear energy density(E = P/v)was introduced as synthetic parameter. The pore decreased gradually with increasing linear energy density. (paper)