The characteristics of chromized 1020 steel with electrical discharge machining and Ni electroplating pretreatments

A uniform and continuous chromized coating on AISI 1020 steel is produced by low-temperature pack chromization (LTPC) with electrical discharge machining and Ni electroplating pretreatments. The anticorrosive performance of the chromized steels is investigated in a 0.5 M H2SO4 solution at room temperature. The testing results indicate that the chromized specimen with electrical discharge machining and Ni electroplating pretreatments exhibits the lowest corrosion current density, 2.16 × 10−8 A cm−2, among the tested specimens. The corrosion resistance of all tested specimens are in the order of bare 1020 < 1020-Cr(700-2) < 1020-Ni-Cr(700-2) < 1020-EDM-Ni-Cr(700-2). Moreover, the 1020-Ni-Cr(700-2) specimen have the best conductivity as a result of the less amount of oxides in the superficial coating.

Research highlights▶ Characteristics of the AISI 1020 steel through pack chromization with pretreatments. ▶ The performance of the chromized coatings in the simulated environments of PEMFCs. ▶ The chromized coatings contain chromium carbides mostly and some chromium nitrides. ▶ Promoting the corrosion resistance and surface conductivity of AISI 1020 steels.