Abstract
In this study, the deformation behavior of hollow cylinder parts fabricated by Laser-Powder Bed Fusion (L-PBF) process was
investigated, using two types of Fe-based alloy powders, 316L stainless steel and maraging steel. For 316L stainless steel, shrinkage
of the outer radius of hollow cylinder parts was observed, especially under conditions with high preheating temperature of the
base plate. On the other hand, expansion of the outer radius of the upper part in hollow cylinder parts were observed for maraging
steel on high preheating temperature conditions of the base plate, and the residual stresses along the building direction on the
outer surface of cylinders were decreased with increasing the preheating temperature. The deformation behavior of 316L stainless
steel hollow cylinder during L-PBF process can mainly be explained by the accumulation of residual stress during building, and
thermal shrinking from preheating temperature to room temperature after building. In the case of building of maraging steel hollow
cylinder at the high preheating temperatures, the deformation behavior can be explained mainly by the expansion due to martensitic
transformation after cooling from the preheating temperature to room temperature and the deformation constraint by the base plate.
