Influences of scanning paths on sls part qualities

摘要

In the SLS process, the scanning path is oe of the most important processing factors. The simplest scanning path is raster scanning, but it has been demonstrated that it was not best choice for getting desired part quality. In this paper, it was investigatedseveral different scanning ways for rectangulr and circular sections. The research have been demonstrated that in the same processing conditions, the different scanning pathscan result different dffects on part's bending strength, size enlargement, shape deformation, layer delimitation, that was basically due to the different residual patterns. For rectangular section, it was studied three scanning paths: the longest edge scanning, shortest edge scanning and contour scanning path. The table 1 shows the comparison ofthe part's bending strength and size enlargement produced with different scanning paths. For circular section, it was discussed two scanning ways: centripetal and centrifugal scanning paths. The experients show that centripetal scanning path is better than centrifugal scanning path. When sintering a single circular slice of mixture of metal and polymer, using centripetal path can result a smooth and flat slice; but hen using centrifugal scanning path, the slice was diformed very largely. When building a cylinder, the result is almost the same as above, the centripetal scanning produced the better binding strength and good surface quality. THis pheomena can be explained by the different cooling sequence resulting different residual stress patterns.