2022 Fiscal Year Research-status Report
Electrodeposition of supersaturated aluminum-based solid solutions for maximizing strength and corrosion resistance
| Project/Area Number |
22K14508
|
|---|
| Research Institution | Kyoto University |
|---|
Principal Investigator |
張 澤磊 京都大学, 工学研究科, 特定助教 (90913400)
|
|---|
| Project Period (FY) |
2022-04-01 – 2024-03-31
|
| Keywords | Electrodeposition / Aluminum alloy / Mechanical property / Corrosion resistance |
|---|
| Outline of Annual Research Achievements |
Aluminum (Al) strengthened through alloying followed by the deformation and/or aging is inherently subject to the conflict between strength and corrosion resistance due to coarse intermetallic particles (IMPs) in α-Al matrix. Accordingly, supersaturated solid solutions with a homogenous microstructure are proposed to defeat that conflict.
In the first stage of this research, the Al(Fe) supersaturated solid solutions have been obtained using typical 1-ethyl-3-methylimidazolium chloride ([EMIm]Cl)－aluminum chloride (AlCl3) ionic liquids (ILs), where the coordination of dissolving Fe2+ have been clarified by spectroscopies together with ab initio calculation. The TEM and XRD demonstrated that Fe (1.5－14.1 at.%) could completely dissolve into α-Al matrix, and its contents were controlled via iron(II) chloride (FeCl2) concentrations in baths. Especially, these Al(Fe) alloys with higher Fe solid solubility prove to attain a simultaneous improvement in hardness and pitting corrosion resistance based on nanoindentation and cyclic polarization curves respectively.
In addition, our newly developed quaternary phosphonium-based ILs ([P14,6,6,6]Cl－AlCl3) could give Al(Si, 3－6 at.%) supersaturated solid solutions at room temperature, while their properties including hardness and corrosion resistance require further studies.
|
| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
To date, these two items (Electrodeposition of smooth and dense Al(M) solid solutions; Clarify the role of M in strength and corrosion resistance of Al(M)) of the research plan for this project, which involve the use of Fe as the solute element, have been completed. That will serve as a guide for the study of other solute elements.
|
| Strategy for Future Research Activity |
Next, this study will take a deep insight into the precipitation behavior of IMPs, figuring out how their shape, size, and distribution vary with the temperature and time during the heat treatment. The effect of IMPs on strength and corrosion resistance will also be investigated.
|
