Aluminum and aluminum alloy electroplated coatings
In certain aspects, a coated steel substrate comprises a single or multiple-layer electroplated aluminum coating over a steel substrate. The multiple-layer electroplated aluminum coating comprises one or more porous layers and one or more compact layers. The one or more porous layers comprise a material selected from a group consisting of aluminum and aluminum alloys. The one or more compact layers comprise a material selected from a group consisting of aluminum and aluminum alloys. In certain aspects, a method of depositing a multiple-layer aluminum coating over a steel substrate includes electroplating one or more porous aluminum layers over the steel substrate. The one or more porous aluminum layers comprise a material selected from a group consisting of aluminum and aluminum alloys. One or more compact aluminum layers are electroplated over the steel substrate. The one or more compact aluminum layers comprise a material selected from a group consisting of aluminum and aluminum alloys.
1. A coated steel substrate, comprising:
a steel substrate; and
a multiple-layer electroplated aluminum coating over the steel substrate, the multiple-layer electroplated aluminum coating comprising,
a porous layer disposed on the steel substrate, the porous layer comprising a material selected from the group consisting of aluminum and aluminum alloy, wherein the porous layer has a plurality of pores having a pore size of about 2 μm or more, and
a compact layer disposed on the porous layer, the compact layer comprising a material selected from the group consisting of aluminum and aluminum alloy, wherein the compact layer comprises a plurality of pores having a pore size of about 0.2 μm or less.
2. The coated steel substrate of claim 1 , further comprising additional compact layers disposed on additional porous layers compact layer.
3. The coated steel substrate of claim 1 , wherein the porous layer has a thickness from about 0.3 μm to about 3 μm and the compact layer has a thickness from about 0.3 μm to about 3 μm.
4. The coated steel substrate of claim 1 , wherein the multiple-layer electroplated aluminum coating comprises from one to fifty porous layers and from one to fifty compact layers.
5. The coated steel substrate of claim 1 , wherein the multiple-layer electroplated aluminum coating is configured to provide sacrificial corrosion protection of over 1,000 hrs under ASTM B 117.
6. The coated steel substrate of claim 1 , wherein the multiple-layer electroplated aluminum coating passes a hydrogen embrittlement (HE) test performed according to ASTM F 519 using Type 1a.1 specimens having a notch.
7. The coated steel substrate of claim 1 , wherein multiple-layer electroplated aluminum coating comprises a total thickness of about 10 μm to about 40 μm.
8. A coated steel substrate, comprising:
a high strength steel substrate; and
a multiple-layer electroplated aluminum coating over the steel substrate, the multiple-layer electroplated aluminum coating comprising at least one porous layer and at least one compact layer, the at least one porous layer comprising a material selected from a group consisting of aluminum and aluminum alloys, and the at least one compact layer comprising a material selected from a group consisting of aluminum and aluminum alloys,
wherein the at least one porous layer has a plurality of pores having a pore size of about 2 μm or more,
wherein the at least one porous layer has a thickness from about 0.3 μm to about 3 μm,
wherein the at least one compact layer has a thickness from about 0.3 μm to about 3 μm, and
wherein the compact layer comprises a plurality of pores having a pore size of about 0.2 μm or less.
9. The coated steel substrate of claim 8 , wherein the multiple-layer electroplated aluminum coating is configured to provide sacrificial corrosion protection of over 1,000 hrs under ASTM B 117.
10. The coated steel substrate of claim 8 , wherein the multiple-layer electroplated aluminum coating passes a hydrogen embrittlement (HE) test performed according to ASTM F 519 using Type 1a.1 specimens having a notch.
11. The coated steel substrate of claim 8 , wherein the at least one porous layer is electroplated by direct current and wherein the at least one compact layer is electroplated by pulsed current, wherein the multiple-layer electroplated aluminum coating is configured to provide corrosion resistance to the steel substrate in neutral water and in salt water.
12. The coated steel substrate of claim 8 , wherein the multiple layer aluminum coating has a thickness from about 10 μm to about 40 μm and provides sacrificial corrosion protection.
13. A component, comprising:
a substrate;
an electroplated aluminum coating disposed over the substrate, wherein
the electroplated aluminum coating is a multiple layer aluminum coating comprising at least one first electroplated aluminum layer, wherein the first electroplated aluminum layer comprises a plurality of pores having a pore size of about 2 μm or more, and
at least one second electroplated aluminum layer disposed over the first electroplated aluminum layer, wherein the second electroplated aluminum layer comprises a plurality of pores having a pore size of about 0.2 μm or less, and
the electroplated aluminum coating comprises a total thickness of about 10 μm to about 40 μm.
14. The component of claim 13 , wherein the substrate is a steel substrate selected from the group consisting of low-carbon steel, medium-carbon steel, high-carbon steel, low-alloy steel, high-alloy steel, and combinations thereof.
15. The component of claim 14 , wherein the electroplated aluminum coating comprises from one to fifty first electroplated aluminum layer layers and from one to fifty second electroplated aluminum layer layers.
16. The component of claim 15 , wherein the at least one first electroplated aluminum layer has a thickness from about 0.3 μm to about 3 μm and the at least one second electroplated aluminum layer has a thickness from about 0.3 μm to about 3 μm.
17. The component of claim 16 , wherein the electroplated aluminum coating is configured to provide sacrificial corrosion protection of over 1,000 hrs under ASTM B 117.
18. The component of claim 17 , wherein the electroplated aluminum coating passes a hydrogen embrittlement (HE) test performed according to ASTM F 519 using Type 1a.1 specimens having a notch.
19. The component of claim 18 , wherein the substrate is a part of any one or more of an aircraft, a spacecraft, a water-craft, a land vehicle, an engine, a propulsion structure, a space re-entry vehicle, a power-generation turbine, or any other metal component.
20. The coated steel substrate of claim 8 , wherein the substrate is a steel substrate selected from the group consisting of low-carbon steel, medium-carbon steel, high-carbon steel, low-alloy steel, high-alloy steel, and combinations thereof.