Thermal Stresses in Direct Metal Laser Sintering

Abstract

In Direct Metal Laser Sintering objects are created by sequential sintering loose metal powder particles by means of laser technology. When the laser sintering process involves temperature gradients, thermal stresses develop. Corresponding residual stresses induce warping of the densified structure leading to unacceptable tolerance losses. This paper examines the role of laser beam scan patterns on the resulting stresses and warpage of direct metal laser sintered plate-shaped specimens. The effects of a large variety of laser sintering parameters are described. It can be shown that the optimization of process conditions and material aspects results in a significant reduction of thermal stresses.