Influence of Cr on the interfacial boride reaction between Fe-Cr-B cast steel and molten aluminium

摘要

The influence of the Cr content of Fe-Cr-B cast steel on the interfacial reaction between M2B-type (M = Fe, Cr) boride and molten aluminium was studied. Different types of the M2B phases behaved differently in molten aluminium, with (Cr,Fe)(2)B forming periodic layered structures (PLSs), which improves the corrosion resistance of the steel. In particular, it is shown that alternating-layer phases in a PLS are not formed initially. Instead the preferential leaching of Fe atoms from (Cr,Fe)(2)B, accompanied by the inward diffusion of Al atoms, resulted in the initial formation of a single-phase layer of the Cr-B-Al phase.