Hot-dip Zn-Al-Mg-Si-Cr alloy coated steel material with excellent corrosion resistance

摘要

Provided is a hot-dip Zn-Al-Mg-Cr alloy coated steel material with excellent corrosion resistance. The coated steel material is a steel material provided with a Zn-Al-Mg-Cr alloy coating, which has an interfacial alloy layer in the coating/steel interface. The interfacial alloy layer consists of constituent elements of the coating and Fe, and has a multi-layer structure comprising an Al-Fe based alloy layer and an Al-Fe-Si based alloy layer. The Al-Fe-Si based alloy layer contains Cr.