Treatment for improved magnesium surface corrosion-resistance

• US 20040034109A1
• Filed: 08/15/2003
• Published: 02/19/2004
• Est. Priority Date: 06/28/2001
• Status: Abandoned Application

• Current Assignee: Algat Sherutey Gimur Teufati-Kibbutz Alonim
• Original Assignee: Algat Sherutey Gimur Teufati-Kibbutz Alonim
• Inventors: Ostrovsky, Ilya
• Application Number:
  US10/641,133
• Publication Number:
  US 20040034109A1
• Time in Patent Office: Days
• US Class Current: 516/38
• CPC Class Codes: C23C 18/36 using hypophosphites
• CPC Class Codes: C23C 22/57 Treatment of magnesium or alloys based thereon
• CPC Class Codes: C23C 2222/20 Use of solutions containing silanes
• CPC Class Codes: C25D 11/026 Anodisation with spark discharge
• CPC Class Codes: C25D 11/30 of magnesium or alloys based thereon
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane

Abstract

A method, a composition and a method for making the composition for increasing the corrosion resistance of a magnesium or magnesium alloy surface is disclosed. The composition is a water/organic solution of one or more hydrolyzed silanes. By binding silane moieties to the magnesium surface, an anti-corrosion coating on a magnesium workpiece is produced. A complementary method, composition and method for preparing the composition for treating a metal surface to increase corrosion resistance is disclosed. The composition is an aqueous hydrogen fluoride solution with a non-ionic surfactant.

Claims

1. A composition useful for treating of a metal or metal alloy surface comprising:

a. hydrogen fluoride (HF);

b. a nonionic surfactant; and

c. water.

2. The composition of claim 1 having a HF content of between about 5% and about 40%, by weight.

3. The composition of claim 2 having a HF content of between about 10% and about 30%, by weight.

4. The composition of claim 3 having a nonionic surfactant content of between about 20 ppm and about 1000 ppm.

5. The composition of claim 4 having a nonionic surfactant content of between about 40 ppm and about 500 ppm.

6. The composition of claim 5 having a nonionic surfactant content of between about 100 ppm and about 400 ppm.

7. The composition of claim 1 wherein said nonionic surfactant is a polyoxyalkylene ether.

8. The composition of claim 7 wherein said polyoxyalkylene ether is a polyoxyethylene ether.

9. The composition of claim 8 wherein said surfactant is chosen from a group consisting of polyoxyethylene oleyl ethers, polyoxyethylene cetyl ethers, polyoxyethylene stearyl ethers, polyoxyethylene dodecyl ethers.

10. The composition of claim 9 wherein said surfactant is polyoxyethylene(10) oleyl ether.

11. A method of treating a workpiece comprising:

a. providing a surface of the workpiece, said surface chosen from the group consisting of magnesium and magnesium alloy; and

b. contacting said surface with a treatment solution, said treatment solution including hydrogen fluoride (HF) and a nonionic surfactant in an aqueous solution.

12. The method of claim 11 wherein an HF content of said treatment solution is between about 5% and about 40%, by weight.

13. The composition of claim 12 having a HF content of between about 10% and about 30%, by weight.

14. The method of claim 11 wherein a nonionic surfactant content of said treatment solution is between about 20 ppm and about 1000 ppm.

15. The composition of claim 14 having a nonionic surfactant content of between about 40 ppm and about 500 ppm.

16. The composition of claim 15 having a nonionic surfactant content of between about 100 ppm and about 400 ppm.

17. The method of claim 11 wherein said nonionic surfactant is a polyoxyalkylene ether.

18. The composition of claim 17 wherein said polyoxyalkylene ether is a polyoxyethylene ether.

19. The composition of claim 18 wherein said surfactant is chosen from a group consisting of polyoxyethylene oleyl ethers, polyoxyethylene cetyl ethers, polyoxyethylene stearyl ethers, polyoxyethylene dodecyl ethers.

20. The composition of claim 19 wherein said surfactant is polyoxyethylene(10) oleyl ether.

21. The method of claim 11 wherein said surface is a corroded surface.

22. A method for the preparation of a treatment solution useful for the treating of a magnesium or magnesium alloy surface comprising combining hydrogen fluoride (HF) and a nonionic surfactant with water.

23. The method of claim 22 wherein an amount of HF is combined so that the treatment solution has an HF content of between about 5% and about 40%, by weight.

24. The method of claim 22 wherein an amount of nonionic surfactant is combined so that the treatment solution has a nonionic surfactant content of between about 20 ppm and about 1000 ppm.

25. The method of claim 22 wherein said nonionic surfactant is a polyoxyalkylene ether.