Galvanized steel sheet
A galvanized steel sheet comprising a steel sheet containing C: 0.05 to 0.30%, Si: 0.01 to 3.00%, Mn: 0.80 to 3.00%, and Al: 0.010 to 2.000% and having a thickness of 0.10 to 0.95 mm, and a galvanized layer on the steel sheet, wherein a tensile strength is 550 to 1500 MPa, and, when defining a thickness of an internal oxide layer per surface of the steel sheet as “A” (μm), a thickness of a decarburized layer per surface of the steel sheet as “B” (μm), and a thickness of the steel sheet as “t” (μm), A/B: 0.01 to 0.50 and B/t: 0.001 to 0.200.
1 . A galvanized steel sheet comprising
a steel sheet having a chemical composition containing, by mass %,
C: 0.05 to 0.30%,
Si: 0.01 to 3.00%,
Mn: 0.80 to 3.00%,
Al: 0.010 to 2.000%,
P: 0.100% or less,
S: 0.100% or less,
N: 0.0300% or less,
O: 0.010% or less,
B: 0 to 0.0100%,
Ti: 0 to 0.100%,
Nb: 0 to 0.100%,
V: 0 to 0.10%,
Cr: 0 to 1.00%,
Ni: 0 to 0.10%,
Cu: 0 to 0.10%,
Mo: 0 to 0.50%,
W: 0 to 0.50%,
Ca: 0 to 0.100%,
Mg: 0 to 0.100%,
Zr: 0 to 0.100%,
Hf: 0 to 0.100%,
REM: 0 to 0.100% and
a balance of Fe and impurities, wherein the steel sheet has a thickness of 0.10 to 0.95 mm, and
a galvanized layer formed on at least one surface of the steel sheet,
wherein
a tensile strength is 550 to 1500 MPa,
when defining a thickness of an internal oxide layer per surface of the steel sheet as “A” (μm), a thickness of a decarburized layer per surface of the steel sheet as “B” (μm), and the thickness of the steel sheet as “t” (μm),
A/B: 0.01 to 0.50 and
B/t: 0.001 to 0.200,
a width of the steel sheet is 1500 to 3000 mm, and,
when defining a standard deviation in a width direction of a thickness of the internal oxide layer as “a” (μm) and a standard deviation in a width direction of a thickness of the decarburized layer as “b” (μm),
A: 1.0 μm or more,
B: 10 μm or more,
a/A: 0.15 or less, and
b/B: 0.20 or less.
2 . The galvanized steel sheet according to claim 1 , wherein, by mass %, Si+Mn: 5.00% or less and Si/Mn: 1.50 or less.
3 . The galvanized steel sheet according to claim 1 , wherein the steel sheet has a chemical composition containing, by mass %, one or more of
B: 0.0001 to 0.0100%,
Ti: 0.001 to 0.100%,
Nb: 0.001 to 0.100%,
Cr: 0.01 to 1.00%,
Mo: 0.01 to 0.50%, and
W: 0.01 to 0.50%.
4 . The galvanized steel sheet according to claim 1 , wherein the steel sheet has a chemical composition containing, by mass %, one or more of
V: 0.01 to 0.10%,
Ni: 0.01 to 0.10%,
Cu: 0.01 to 0.10%,
Ca: 0.001 to 0.100%,
Mg: 0.001 to 0.100%,
Zr: 0.001 to 0.100%,
Hf: 0.001 to 0.100%, and
REM: 0.001 to 0.100%.
5 . The galvanized steel sheet according to claim 1 , wherein the galvanized steel sheet is a hot dip galvannealed steel sheet, a chemical composition of the galvanized layer contains, by mass %, Fe: 5 to 15%, Al: 0.01 to 1% and a balance of Zn and impurities, and an amount of deposition per surface of the galvanized layer is 10 to 100 g/m 2 .
6 . The galvanized steel sheet according to claim 2 , wherein the steel sheet has a chemical composition containing, by mass %, one or more of
B: 0.0001 to 0.0100%,
Ti: 0.001 to 0.100%,
Nb: 0.001 to 0.100%,
Cr: 0.01 to 1.00%,
Mo: 0.01 to 0.50%, and
W: 0.01 to 0.50%.
7 . The galvanized steel sheet according to claim 2 , wherein the steel sheet has a chemical composition containing, by mass %, one or more of
V: 0.01 to 0.10%,
Ni: 0.01 to 0.10%,
Cu: 0.01 to 0.10%,
Ca: 0.001 to 0.100%,
Mg: 0.001 to 0.100%,
Zr: 0.001 to 0.100%,
Hf: 0.001 to 0.100%, and
REM: 0.001 to 0.100%.
8 . The galvanized steel sheet according to claim 3 , wherein the steel sheet has a chemical composition containing, by mass %, one or more of
V: 0.01 to 0.10%,
Ni: 0.01 to 0.10%,
Cu: 0.01 to 0.10%,
Ca: 0.001 to 0.100%,
Mg: 0.001 to 0.100%,
Zr: 0.001 to 0.100%,
Hf: 0.001 to 0.100%, and
REM: 0.001 to 0.100%.
9 . The galvanized steel sheet according to claim 2 , wherein the galvanized steel sheet is a hot dip galvannealed steel sheet, a chemical composition of the galvanized layer contains, by mass %, Fe: 5 to 15%, Al: 0.01 to 1% and a balance of Zn and impurities, and an amount of deposition per surface of the galvanized layer is 10 to 100 g/m 2 .
10 . The galvanized steel sheet according to claim 3 , wherein the galvanized steel sheet is a hot dip galvannealed steel sheet, a chemical composition of the galvanized layer contains, by mass %, Fe: 5 to 15%, Al: 0.01 to 1% and a balance of Zn and impurities, and an amount of deposition per surface of the galvanized layer is 10 to 100 g/m 2 .
11 . The galvanized steel sheet according to claim 4 , wherein the galvanized steel sheet is a hot dip galvannealed steel sheet, a chemical composition of the galvanized layer contains, by mass %, Fe: 5 to 15%, Al: 0.01 to 1% and a balance of Zn and impurities, and an amount of deposition per surface of the galvanized layer is 10 to 100 g/m 2 .