Solution composition and method for single-bath post treatment of substrate
Disclosed is a solution composition which may be used for a single-bath electrochemical passivation and a method using the same. The solution composition includes a metal cation, a metal-oxide anion; and an organic ligand, and optionally includes a non-metallic oxide anion or a polymer. The solution composition may prevent undesired precipitation of metal oxides before performing passivation. In addition, the method of passivation using the solution composition in a single-bath use is also provided.
1. An article manufactured by a method of single-bath passivation post-treatment, comprising:
preparing a solution composition;
applying the solution composition to a substrate;
applying an electric current to the substrate to perform an electrode deposition;
wherein the solution composition comprises:
a metal cation selected from the group consisting of Ce 3+ , Y 3+ , La 3+ , Pr 3+ , Sm 3+ , and mixtures thereof;
a metal-oxide anion selected from the group consisting of VO 3 − , MoO 4 2− , WO 4 2− , and mixtures thereof;
an organic ligand selected from the group consisting of acetic acid, lactic acid, citric acid, oxalic acid, salicylic acid, tartaric acid, ethylenediaminetetraacetic acid (EDTA), and mixtures thereof;
a non-metallic oxide anion selected from the group consisting of PO 4 3− , SiO 3 − , B 2 O 4 2− , and mixtures thereof; and
a polymer selected from the group consisting of polyacrylic acid, polyol, polyethylene glycol, and mixtures thereof;
wherein the substrate comprises a first metallic-oxide film formed from the metal cation, and a second metallic-oxide film formed from the metal-oxide anion or a non-metallic-oxide film formed from the non-metallic oxide anion.
2. The article of claim 1 , wherein the electric current applied to the substrate is a forward pulse electric current or a reverse pulse electric current.
3. The article of claim 1 , wherein the method further comprises applying a secondary electric current to the substrate in the solution composition to perform a second electrode deposition.
4. The article of claim 1 , wherein the electric current is 0.06 to 1.0 mA/cm 2 .
5. The article of claim 1 , wherein the solution composition has a pH of about 7.0 to about 11.0.
6. The article of claim 1 , wherein the solution composition has a temperature of 25 to 50° C.
7. The article of claim 1 , wherein the solution composition is aerated with air or oxygen gas during the electrode deposition.
8. The article of claim 1 , wherein the substrate is a coated substrate.
9. The article of claim 8 , wherein the substrate is coated Zn or coated Zn-Ni alloy.
10. The article of claim 1 , wherein the substrate is aluminum or steel.
11. The article of claim 1 , wherein the substrate is an aircraft part.
12. The article of claim 1 , wherein the substrate comprises the first metallic-oxide film formed from the metal cation, and the second metallic-oxide film formed from the metal-oxide anion, and the non-metallic-oxide film formed from the non-metallic oxide anion.