High-strength hot-dip galvanized steel sheet and high-strength alloyed hot-dip galvanized steel sheet having excellent formability and small material anisotropy with ultimate tensile strength of 980 MPa or more

1. A high-strength hot-dip galvanized steel sheet having small material anisotropy and excellent formability with an ultimate tensile strength of 980 MPa or more, the hot-dip galvanized steel sheet comprising a hot-dip galvanized layer formed on a surface of a base steel sheet,

wherein the base steel sheet contains: by mass %,

C: 0.1 to less than 0.40%;

Si: 0.5 to 3.0%;

Mn: 1.5 to 3.0%;

O: 0.0001 to 0.006%;

P: 0.0001 to 0.04%;

S: 0.0001 to 0.01%;

Al: 0.0005 to 2.0%;

N: 0.0005 to 0.01%; and

a balance including Fe and inevitable impurities,

a microstructure of the base steel sheet contains ferrite of 40% or more, contains residual austenite of 8 to 27%, by volume fraction, and contains bainite and a balance being martensite or less than 10% of pearlite,

an average value of pole densities of orientation groups {100} <011> to {223} <110> represented by each of crystal orientations {100} <011>, {116} <110>, {114} <110>, {113} <110>, {112} <110>, {335} <110>, and {223} <110> in a sheet thickness range of ⅝ to ⅜ from the surface of the base steel sheet is 6.5 or less and a pole density of a crystal orientation {332} <113> is 5.0 or less, and

the hot-dip galvanized layer contains Fe: less than 7 mass % and a balance including Zn, Al, and inevitable impurities.

2. The high-strength hot-dip galvanized steel sheet having the small material anisotropy and the excellent formability with the ultimate tensile strength of 980 MPa or more according to claim 1 , wherein the base steel sheet further contains one or two or more of: by mass %,

Cr: 0.05 to 1.0%;

Mo: 0.01 to 1.0%;

Ni: 0.05 to 1.0%;

Cu: 0.05 to 1.0%;

Nb: 0.005 to 0.3%;

Ti: 0.005 to 0.3%;

V: 0.005 to 0.5%; and

B: 0.0001 to 0.01%.

3. The high-strength hot-dip galvanized steel sheet having the small material anisotropy and the excellent formability with the ultimate tensile strength of 980 MPa or more according to claim 1 , wherein the base steel sheet further contains, by mass %, 0.0005 to 0.04% in total of one or two or more selected from Ca, Mg, and REM.

4. A high-strength alloyed hot-dip galvanized steel sheet having small material anisotropy and excellent formability with an ultimate tensile strength of 980 MPa or more, the alloyed hot-dip galvanized steel sheet comprising an alloyed hot-dip galvanized layer formed on a surface of a base steel sheet,

wherein the base steel sheet contains: by mass %,

C: 0.10 to less than 0.4%;

Si: 0.5 to 3.0%;

Mn: 1.5 to 3.0%;

O: 0.0001 to 0.006%;

P: 0.0001 to 0.04%;

S: 0.0001 to 0.01%;

Al: 0.0005 to 2.0%;

N: 0.0005 to 0.01%; and

a balance including Fe and inevitable impurities,

a microstructure of the base steel sheet contains ferrite of 40% or more, contains residual austenite of 8 to 27%, by volume fraction, and contains bainite and a balance being martensite or less than 10% of pearlite,

an average value of pole densities of orientation groups {100} <011> to {223} <110> represented by each of crystal orientations {100} <011>, {116} <110>, {114} <110>, {113} <110>, {112} <110>, {335} <110>, and {223} <110> in a sheet thickness range of ⅝ to ⅜ from the surface of the base steel sheet is 6.5 or less and a pole density of a crystal orientation {332} <113> is 5.0 or less, and

the alloyed hot-dip galvanized layer contains Fe: 7 to 15 mass % and a balance including Zn, Al, and inevitable impurities.

5. The high-strength alloyed hot-dip galvanized steel sheet having the small material anisotropy and the excellent formability with the ultimate tensile strength of 980 MPa or more according to claim 4 , wherein the base steel sheet further contains one or two or more of: by mass %,

Cr: 0.05 to 1.0%;

Mo: 0.01 to 1.0%;

Ni: 0.05 to 1.0%;

Cu: 0.05 to 1.0%;

Nb: 0.005 to 0.3%;

Ti: 0.005 to 0.3%;

V: 0.005 to 0.5%; and

B: 0.0001 to 0.01%.

6. The high-strength alloyed hot-dip galvanized steel sheet having the small material anisotropy and the excellent formability with the ultimate tensile strength of 980 MPa or more according to claim 4 , wherein the base steel sheet further contains, by mass %, 0.0005 to 0.04% in total of one or two or more selected from Ca, Mg, and REM.