Decreased porosity and improved corrosion resistance of B4C-filled Al slabs via hot cross-rolling

The study aims to describe the effect of the hot cross-rolling process on the physical and corrosion properties of hot-pressed Al/30 wt%B4C composite. The starting powders were milled by planetary mill machine and then were sintered by a hot pressing machine at 600 °C for 1 h under 50 MPa pressure in a vacuum. Hot cross-rolling was carried out in 8 and 16 passes after soaking at 773 K (500 °C) for 20 min. Sample characterization takes place through electrochemical corrosion tests, X-ray diffraction, scanning electron microscope and density. The results showed that performing the hot cross-rolling process on the samples leads to an increase in corrosion resistance and density. The 50% hot cross rolled sample had the highest corrosion resistance and density value. The corrosion resistance of the samples was reduced in H3BO3, NaCl and NaOH solutions, respectively. In H3BO3 solution, the continuity of the protective oxide layer is largely preserved, which leads to higher corrosion resistance in this solution than other solutions. •Performing of hot cross rolling leads to an increase in residual compressive stresses, corrosion resistance and density.•The 50% hot cross rolled sample had the highest corrosion resistance and density value.•The corrosion resistance of the samples was reduced in the H3BO3, NaCl and NaOH solutions, respectively.•In the H3BO3, the continuity of the protective layer is largely preserved, which leads to higher corrosion resistance.