Enhanced Performance of Austenitic Oxide Dispersion-Strengthened 316L Steel: A Study on YO Reinforcement and Corrosion Behaviour.

This study explores the mechanical and corrosion properties of yttria-reinforced 316L stainless steel. Powder precursor materials were prepared using mechanical alloying. Varying yttria (YO) contents (1, 3, and 5 wt%) were used to assess its impact on the steel's properties. X-ray diffraction and scanning electron microscopy confirmed the successful dispersion of YO within the matrix, with the formation of chromium carbides during spark plasma sintering (SPS). The mechanical properties, including hardness and compressive yield strength, improved with increasing YO contents, with the highest strength observed in the 316L-5YO sample. However, corrosion resistance decreased with higher yttria concentrations. The 3 wt% YO sample exhibited the highest corrosion rate due to localized corrosion in areas enriched with oxide particles and chromium carbides. Electrochemical testing revealed that carbide formation and Cr-depleted regions from SPS processing contributed to the corrosion behaviour. These findings suggest that while yttria reinforcement enhances mechanical strength, optimizing the YO content and processing methods is crucial to balance both mechanical and corrosion performance in ODS 316L stainless steel.