Corrosion behaviour of Tribaloy T400 coating prepared by laser cladding in molten aluminium alloys

Abstract

Corrosion of molten Aluminium alloys is an important reason to lead the failure of moulds. The Tribaloy T400 coating was prepared on H13 steel by laser cladding to investigate corrosion behaviour in molten A356 Aluminium alloys at 993 K for different periods. The main phases in the Tribaloy T400 coating were primary Co-rich FCC phase and Laves phase (Co7Mo6 and Co3Mo2Si). The Tribaloy T400 coating maintain its surface integrity after immersion in molten Aluminium alloy for 7d. The corrosion resistance was improved significantly compared to H13 steel substrate. The Vickers hardness of the coating was increased from 686 to 727 HV0.3, which could be attributed to the obvious aging hardening effect in Tribaloy T400 coating.