Prevention of bumpy texture forming on side of laser sintered parts

Abstract

It sometimes happens that side of laser sintered parts is achieved a poor surface finish called ″orange peel″, which is unintentional bumpy texture. This paper reports that the quality of surface finish was caused by semi-sintered powder sticking on the side of laser sintered parts. It was found that the formation of bumpy structure on the side depended on whether un-melt powder stick to the side or not. In order to control semi-sintered powder sticking on the side, additional low-power laser drawing was operated around the specimen layer by layer. As result, frequency of a good surface finish, which range of Sa is under 20 micrometer increased compared to non-additional laser drawing.