Plated steel sheet for hot press forming having excellent weldability and corrosion resistance, forming member, and manufacturing method thereof

1. A hot-press formed member comprising:

a base steel sheet;

an alloy layer formed on at least one side of the base steel sheet, wherein the alloy layer comprises at least two alloys selected from the group consisting of an Fe—Mn-based alloy, an Fe—Al—Mn-based alloy, an Fe—Al-based alloy, and an Al—Mn-based alloy; and

a composite plating layer formed on at least one side of the base steel sheet, wherein:

the composite plating layer comprises a Mn-based plating layer and an Al-based plating layer alternately formed with the Al-based plating layer being an uppermost layer,

the composite plating layer has a total thickness of 5 μm to 30 μm,

the Mn-based plating layer has a thickness of 5% to 60% of the total thickness of the composite plating layer, and

the Mn-based plating layer comprises at least one selected from the group consisting of chromium (Cr), zinc (Zn), beryllium (Be), magnesium (Mg), calcium (Ca), and titanium (Ti) in an amount of 5 wt % to 20 wt %.

2. The hot-press formed member of claim 1 , wherein the alloy layer comprises an uppermost layer formed of the Fe—Al—Mn-based alloy, the Fe—Al-based alloy, or the Al—Mn-based alloy.

3. The hot-press formed member of claim 1 , wherein the alloy layer further comprises at least one alloy selected from the group consisting of a Zn—Mn-based alloy, a Zn—Fe-based alloy, an Fe—Mn—Al—Mg-based alloy, and an Fe—Mn—Al—Si-based alloy.

4. The hot-press formed member of claim 3 , wherein the alloy layer comprises an uppermost layer formed of the Fe—Al—Mn-based alloy, the Fe—Al-based alloy, the Al—Mn-based alloy, or the Fe—Mn—Al—Si-based alloy.

5. The hot-press formed member of claim 1 , wherein the alloy layer comprises an uppermost layer formed of an Al-containing alloy.

6. The hot-press formed member of claim 1 , wherein surface oxides formed on an outermost surface of the alloy layer have a thickness of 2 μm or less.

7. The hot-press formed member of claim 1 , wherein the base steel sheet comprises a carbon steel sheet including 0.1 wt % to 0.4 wt % of carbon (C), 0.05 wt % to 1.5 wt % of silicon (Si), 0.5 wt % to 3.0 wt % of manganese (Mn), and a balance of iron (Fe) and inevitable impurities.

8. The hot-press formed member of claim 1 , wherein the base steel sheet further comprises at least one selected from the group consisting of 0.001 wt % 0.02 wt % of nitrogen (N), 0.0001 wt % to 0.01 wt % of boron (B), 0.001 wt % to 0.1 wt % of titanium (Ti), 0.001 wt % to 0.1 wt % of niobium (Nb), 0.001 wt % to 0.01 wt % of vanadium (V), 0.001 wt % to 1.0 wt % of chromium (Cr), 0.001 wt % to 1.0 wt % of molybdenum (Mo), 0.001 wt % to 0.1 wt % of antimony (Sb), and 0.001 wt % to 0.3 wt % of tungsten (W).

9. The hot-press formed member of claim 1 , wherein the Mn-based plating layer comprises manganese (Mn) in an amount of 80 wt % or greater.

10. The hot-press formed member of claim 1 , wherein the Al-based plating layer comprises aluminum (Al) in an amount of 80 wt % or greater.

11. The hot-press formed member of claim 1 , wherein the Al-based plating layer comprises at least one selected from the group consisting of zinc (Zn), silicon (Si), magnesium (Mg), and manganese (Mn) in an amount of 20 wt % or less (excluding 0 wt %).

12. The hot-press formed member of claim 1 , wherein the Mn-based plating layer comprises zinc (Zn).

13. The hot-press formed member of claim 1 , wherein the Mn-based plating layer comprises manganese (Mg).

14. The hot-press formed member of claim 1 , wherein the Al-based plating layer comprises silicon (Si).

15. The hot-press formed member of claim 1 , wherein the Al-based plating layer comprises manganese (Mn).