Metal Additive Manufacturing Conference - MAMC 2021

Due to the raster heat inputs, steep temperature gradients and rapid cooling, the selective laser melting (SLM) process generally induces high residual stresses heterogeneity across the fabricated parts. In the case of gears, such variations on the teeth flank may have a negative effect on the fatigue behavior. This study analyzes the influence of residual stresses heterogeneity induced by SLM on the contact fatigue behavior of carburizing steel 20MnCr5 samples reproducing gear applications. Residual stress maps and depth profiles obtained by X-ray diffraction along the dimensions of rod-shaped samples are correlated to ball-rod contact fatigue results. The fatigue scatter is then discussed in view of the residual stress heterogeneity.