INVESTIGATION OF THE EFFECT OF SCAN VECTOR LENGTH ON RESIDUAL STRESSES IN SELECTIVE LASER MELTING OF MARAGING STEEL 300

Abstract

Selective laser melting scanning strategies influence the quality characteristics of parts, such as form accuracy and residual stresses. Previous research on the effect of laser scanning strategy parameters (such as scan vector length) demonstrates that residual stresses decrease with scan vector length reduction. However, most of these studies overlook the associated porosity and how this can contribute to stress relief. In this work, three scan vector lengths were compared to evaluate their impact on residual stresses, achievable part density, and scanning time. Reducing the scan vector length generally lowers residual stresses magnitudes, but introduces porosity as a result of localised overheating.

Keywords

• selective laser melting
• residual stresses
• porosity
• neutron diffraction