Effects of inclination angle on surface roughness and corrosion properties of selective laser melted 316L stainless steel

Abstract

Balling effect is an inevitable defect during Selective laser melting (SLM) process, and it deteriorates the mechanical and corrosion properties of the resulting parts. In this work, the SLM process is used with various inclination angles to fabricate samples. The deep relationship between the selective laser melting process and the corrosion properties of the as-SLM fabricated parts is established to understand the effect of the inclination angle on the surface roughness, microstructure evolution, and corrosion properties of 316L stainless steel components. Results show that the Ra value of fabricated parts increased with increasing inclination angles. Inclination angles play an important role in balling and defect formation. Fabricated parts exhibit a wide passive region in salty environments. The corrosion resistance of the SLM samples after polishing is decreased comparing to that of the unpolished which attribute to porosity and balling behavior. The typical corrosion characterization of polished surface is pitting and localized corrosion, and it mainly origin of pores and balling. Meanwhile, balling behavior accelerated corrosion rates of non-polished parts.