Evaluation of microstructure, mechanical, and corrosion properties of SS316L/Al2O3 composites produced by hot pressing

In this paper, Al2O3 reinforced SS316L matrix composites were fabricated by powder metallurgy technique. The high energy ball milling effect of the Al2O3 with varying contents, i.e., 5, 10, and 15 wt%, on the mechanical properties, corrosion resistance, and microstructure of the composite were investigated. As the Al2O3 content changed from 0 to 10%, the crystallite size of the composite powders decreased from 22.6 nm to 4.29 nm. The corrosion resistance of composites was determined by the Tafel method. The corrosion process of composites in 3.5 wt% NaCl solution indicates that the corrosion rate (0.062 mm/y) of the composite containing 10 wt % Al2O3 were much lower than pure SS316L (0.156 mm/y) and SS316L/15 wt% Al2O3 composite (0.200 mm/y). The Al2O3 content has an important effect on the reduction in the particle size, the average crystallite size of the composite powders, and the improvement in the corrosion and mechanical properties of the composites. [Display omitted] •Using mechanical milling and hot-pressing techniques are produced the composites.•The distribution of ceramic reinforcements into the matrix is investigated.•Optimum Al2O3 content for the excellent crystallite and particle size is 10% wt.•The severe corrosion results are observed after reinforced with 10% wt. Al2O3.