Hot dip galvannealed steel material having an zinc alloy plated layer containing at least 12% magnesium

摘要

Disclosed is a high corrosion resistance hot dip galvanised steel material having an alloy plated layer containing zinc in an amount of 35 mass % or more and magnesium in an amount of 12 to 60 mass % and Al in an amount of 0.07 to 45%, wherein said alloy plated layer contains a non-equilibrium phase with a heat capacity by differential scanning calorimetry of 1 J/g or more.