Alloyed hot-dip galvanized steel sheet and method of manufacturing the same

1. An alloyed hot-dip galvanized steel sheet comprising a base steel sheet,

wherein the base steel sheet contains, in mass %,

C: more than or equal to 0.05% and less than or equal to 0.50%,

Si: more than or equal to 0.2% and less than or equal to 3.0%,

Mn: more than or equal to 0.5% and less than or equal to 5.0%,

Al: more than or equal to 0.001 and less than or equal to 1.0%,

P: less than or equal to 0.1%,

S: less than or equal to 0.01%,

N: less than or equal to 0.01%, and

the balance including Fe and inevitable impurities,

wherein the alloyed hot-dip galvanized steel sheet is provided with an alloyed hot-dip galvanized layer on a surface of the base steel sheet, the alloyed hot-dip galvanized layer containing, in mass %, Fe: more than or equal to 5% and less than or equal to 15%, and the balance including Zn and inevitable impurities, and having a thickness of more than or equal to 3μm and less than or equal to 30 μm, and

wherein the alloyed hot-dip galvanized steel sheet comprises an A layer immediately under the surface of the base steel sheet, the A layer being formed in the base steel sheet and having a thickness of more than or equal to 2 μm and less than or equal to 20 μm from the surface of the base steel sheet,

the A layer containing more than or equal to 50 vol % of a ferrite structure based on a volume of the A layer and the balance including inevitable structures, and containing, based on a mass of the A layer, more than or equal to 90 mass % of unoxidized Fe, less than or equal to 10 mass % of a total of contents of oxides of Fe, Si, Mn, P, S, and Al, and less than 0.05 mass % of C.

2. The alloyed hot-dip galvanized steel sheet according to claim 1 ,

wherein the base steel sheet further contains one or more of, in mass %,

Cr: more than or equal to 0.05% and less than or equal to 1.0%,

Ni: more than or equal to 0.05% and less than or equal to 1.0%,

Cu: more than or equal to 0.05% and less than or equal to 1.0%,

Nb: more than or equal to 0.005% and less than or equal to 0.3%,

Ti: more than or equal to 0.005% and less than or equal to 0.3%,

V: more than or equal to 0.005% and less than or equal to 0.5%,

B: more than or equal to 0.0001% and less than or equal to 0.01%,

Ca: more than or equal to 0.0005% and less than or equal to 0.04%,

Mg: more than or equal to 0.0005% and less than or equal to 0.04%,

La: more than or equal to 0.0005% and less than or equal to 0.04%,

Ce: more than or equal to 0.0005% and less than or equal to 0.04%, and

Y: more than or equal to 0.0005% and less than or equal to 0.04%.

3. The alloyed hot-dip galvanized steel sheet according to claim 2 ,

wherein the alloyed hot-dip galvanized layer further contains, in mass %, Al: more than or equal to 0.02% and less than or equal to 1.0%.

4. The alloyed hot-dip galvanized steel sheet according to claim 1 ,

wherein the alloyed hot-dip galvanized layer further contains, in mass %, Al: more than or equal to 0.02% and less than or equal to 1.0%.