Plated steel material having excellent friction resistance and white rust resistance and method for preparing same
A plated steel material includes a plated layer containing, by wt %: 0.5 to 14% of Al, 0.5 to 5% of Mg, and the balance being Zn and inevitable impurities. The plated steel material satisfies the following Equation: ([Mg] S −[Mg] 1/2 )/[Mg] 1/2 ≥0.3. [Mg] S means a content (wt %) of Mg in a surface of the plated layer, and [Mg] 1/2 means a content (wt %) of Mg at a ½t position (t represents a thickness of the plated layer) from the surface of the plated layer in a thickness direction.
1. A plated steel material comprising:
a base steel; and
a plated layer formed on a surface of the base steel, the plated layer containing, by wt %: 0.5 to 14% of Al, 0.5 to 5% of Mg, and a balance of Zn and inevitable impurities,
wherein the plated layer satisfies the following Equation 1:
0.3≤([Mg] S −[Mg] 1/2 )/[Mg] 1/2 )/≤0.61, [Equation 1]
where [Mg] S is a content (wt %) of Mg in a surface of the plated layer, [Mg] 1/2 is a content (wt %) of Mg at a (½)t position from the surface of the plated layer, and t is a thickness of the plated layer.
2. The plated steel material of claim 1 , wherein the plated layer has a microstructure containing a Zn single phase structure and a Zn—Al—Mg based intermetallic compound.
3. The plated steel material of claim 2 , wherein the Zn—Al—Mg based intermetallic compound is one or more selected from the group consisting of a Zn/Al/MgZn 2 ternary eutectic structure, a Zn/MgZn 2 binary eutectic structure, a Zn—Al binary eutectic structure, and an MgZn 2 single phase structure.
4. The plated steel material of claim 2 , wherein the Zn single phase structure contains Mg in a content of 0.03 wt % or less.
5. The plated steel material of claim 1 , wherein the plated layer contains, by wt %, 1 to 11% of Al, 1 to 3% of Mg, and a balance of Zn and inevitable impurities.
6. The plated steel material of claim 1 , further comprising: a surface friction coefficient of 0.15 or less.
7. A plated steel material comprising:
a base steel; and
a plated layer formed on a surface of the base steel, the plated layer containing, by wt %: 0.5 to 14% of Al, 0.5 to 5% of Mg, and a balance of Zn and inevitable impurities,
wherein a ratio (C 1 /C 0 ) is in a range of 1.02 to 1.16, where C 0 is an average content (wt %) of Mg in the plated layer, C 1 is a content (wt %) of Mg at a ( 1/7)t position from a surface of the plated layer, and t represents a thickness of the plated layer.
8. The plated steel material of claim 7 , wherein the plated layer has a microstructure contains a Zn single phase structure and a Zn—Al—Mg based intermetallic compound.
9. The plated steel material of claim 8 , wherein the Zn—Al—Mg based intermetallic compound is one or more selected from the group consisting of a Zn/Al/MgZn 2 ternary eutectic structure, a Zn/MgZn 2 binary eutectic structure, a Zn—Al binary eutectic structure, and an MgZn 2 single phase structure.
10. The plated steel material of claim 8 , wherein the Zn single phase structure contains Mg in a content of 0.03 wt % or less.
11. The plated steel material of claim 7 , wherein the plated layer contains, by wt %, 1 to 11% of Al, 1 to 3% of Mg, and a balance of Zn and inevitable impurities.
12. The plated steel material of claim 7 , further comprising: a surface friction coefficient of 0.15 or less.