Alloy-coated steel sheet and manufacturing method thereof
Provided is an alloy-coated steel sheet and a manufacturing method thereof. The alloy-coated steel sheet includes: a steel sheet; and an Al—Mg—Si alloy layer disposed on the steel sheet, wherein the Al—Mg—Si alloy layer has a form in which Mg—Si alloy grains are included in an alloy layer consisting of an Al—Mg alloy phase.
1. An alloy-coated steel sheet comprising:
a steel sheet; and
an Al—Mg—Si alloy layer disposed on the steel sheet,
wherein the Al—Mg—Si alloy layer includes: an Al—Mg alloy phase; and Mg—Si alloy grains surrounded by the Al—Mg alloy phase, and
wherein the Al—Mg alloy phase comprises: Al 3 Mg 2 ; Al 12 Mg 17 ; Al; and Mg solid-solutioned in the Al.
2. The alloy-coated steel sheet of claim 1 , further comprising:
an Al—Si alloy layer disposed between the steel sheet and the Al—Mg—Si alloy layer.
3. The alloy-coated steel sheet of claim 1 , wherein:
the Al—Mg—Si alloy layer has a gradient of a Mg content in the Al—Mg—Si alloy layer.
4. The alloy-coated steel sheet of claim 1 , wherein:
the Al—Mg—Si alloy layer has a Mg content of 15 wt % or more and 90 wt % or less with respect to a total weight of the Al—Mg—Si alloy layer.
5. The alloy-coated steel sheet of claim 1 , wherein:
the Mg—Si alloy grains include Mg 2 Si.
6. The alloy-coated steel sheet of claim 1 , wherein:
the Mg—Si alloy grains are amorphous.
7. The alloy-coated steel sheet of claim 1 , wherein:
the Mg—Si alloy grains have a content of 1 wt % or more and 70 wt % or less with respect to a total weight of the Al—Mg—Si alloy layer.
8. The alloy-coated steel sheet of claim 1 , further comprising:
an Al—Fe—Si alloy layer disposed between the steel sheet and the Al—Mg—Si alloy layer.
9. The alloy-coated steel sheet of claim 1 , further comprising:
an Mg layer or an Al—Mg alloy layer disposed on the Al—Mg—Si alloy layer.