Stress Corrosion Cracking Probability of Selective Laser Melted 316L Austenitic Stainless Steel under the Effect of Grinding Induced Residual Stresses

Surface quality and dimensional tolerances of the selective laser melting (SLM) process are not good enough for many industrial applications grinding as a common finishing introduces surface modifications. Investigation on effect induced residual stress (RS) early stages corrosion cracking (SCC) SLM manufactured 316L austenitic stainless steel was conducted. Potentiodynamic galvanostatic tests in 3.5% NaCl aqueous solution, XRD, SEM energy-dispersive X-ray spectroscopy (EDX) analysis were performed. For annealed specimens with low RS magnitude, dominant observation pit initiation from existing pores growth build direction. medium level, SCC pore sites propagation along melt pool boundaries highest detected RS, crack boundaries, grains, machining marks, observed. Cracks propagated different directions, i.e., near-surface transgranular, transgranular through columnar microstructure. Galvanostatic showed three distinctive regions that corresponded to growth. The synergistic high dislocation density concentration sites, molybdenum segregation, cause susceptibility magnitude.