Electrolyte for electropolishing titanium alloys

Patent metadata

Field	Value
Publication number	US-12338541-B2
Application number	US-202017767557-A
Country	US
Kind code	B2
Filing date	Nov 10, 2020
Priority date	Dec 10, 2019
Publication date	Jun 24, 2025
Grant date	Jun 24, 2025

Abstract

An electrolyte for electropolishing metal surfaces, in particular workpieces, in particular made of titanium or titanium alloys such as nitinol. The electrolyte composition includes methanesulfonic acid and more than one polyhydric alcohol. The content of methanesulfonic acid is less than 15 vol %, the polyhydric alcohols having at least one diol and at least one polyalcohol. The at least one diol accounts for 20 to 65 vol %, and the at least one polyalcohol accounts for 20 to 65 vol %

First claim

What is claimed:

1. An electrolyte, comprising:
methanesulfonic acid; and
more than one polyhydric alcohol,
the content of methanesulfonic acid being less than 15 vol %, the polyhydric alcohols comprising at least one diol and at least one polyalcohol, wherein the at least one polyalcohol comprises more than two OH groups, wherein the at least one diol accounts for 20 to 65 vol %, and the at least one polyalcohol accounts for 20 to 65 vol %.

2. The electrolyte according to claim 1 , wherein the content of methanesulfonic acid is in the range of more than 1 vol % and less than 5 vol %.

3. The electrolyte according to claim 1 , wherein the diol is selected from the group consisting of 1,2-propanediol, 1,3-propanediol, ethylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 2,3-pentanediol, 2,4-pentanediol.

4. An electrolyte, comprising:
methanesulfonic acid; and
more than one polyhydric alcohol,
the content of methanesulfonic acid being less than 15 vol %, the polyhydric alcohols comprising at least one diol and at least one polyalcohol, wherein the at least one diol accounts for 20 to 65 vol %, and the at least one polyalcohol accounts for 20 to 65 vol %, wherein the polyalcohol is selected from the group of triols including a linear C3 to C5 carbon chain.

5. An electrolyte, comprising:
methanesulfonic acid; and
more than one polyhydric alcohol,
the content of methanesulfonic acid being less than 15 vol %, the polyhydric alcohols comprising at least one diol and at least one polyalcohol, wherein the at least one diol accounts for 20 to 65 vol %, and the at least one polyalcohol accounts for 20 to 65 vol %, wherein the polyalcohol is glycerol.

6. An electrolyte, comprising:
methanesulfonic acid; and
more than one polyhydric alcohol,
the content of methanesulfonic acid being less than 15 vol %, the polyhydric alcohols comprising at least one diol and at least one polyalcohol, wherein the at least one diol accounts for 20 to 65 vol %, and the at least one polyalcohol accounts for 20 to 65 vol %, having the following composition:
to 7 vol % methanesulfonic acid; and
33-60 vol % of a diol; and
33-60 vol % glycerol,
wherein the diol is selected from ethylene glycol and 1,2-propanediol.

7. An electropolishing method for a workpiece made of metal, comprising:
providing an electrolyte according to claim 1 ;
introducing a workpiece made of titanium or a titanium alloy, into the electrolyte;
connecting the workpiece to an anode; and
applying a voltage to the workpiece to electropolish the workpiece.

8. The electrolyte of claim 1 , wherein the electrolyte consists of:
the methanesulfonic acid; and
the more than one polyhydric alcohol,
the content of methanesulfonic acid being less than 15 vol %, the polyhydric alcohols comprising at least one diol and at least one polyalcohol, wherein the at least one polyalcohol comprises more than two OH groups, wherein the at least one diol accounts for 20 to 65 vol %, and the at least one polyalcohol accounts for 20 to 65 vol %.

9. The electrolyte according to claim 8 , wherein the content of methanesulfonic acid is in the range of more than 1 vol % and less than 5 vol %.

10. The electrolyte according to claim 8 , wherein the diol is selected from the group consisting of 1,2-propanediol, 1,3-propanediol, ethylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 2,3-pentanediol, 2,4-pentanediol.

11. The electrolyte according to claim 8 , wherein the polyalcohol is selected from the group of triols including a linear C3 to C5 carbon chain.

12. The electrolyte according to claim 8 , wherein the polyalcohol is glycerol.

13. The electrolyte according to claim 8 , having the following composition:
1 to 7 vol % methanesulfonic acid; and
33-60 vol % of a diol; and
33-60 vol % glycerol,
wherein the diol is selected from ethylene glycol and 1,2-propanediol.

Assignees

• Biotronik Ag

Inventors

• Litschko Robert

Classifications

• C25F3/08

  of refractory metals · CPC title

• C25F1/08

  Refractory metals · CPC title

• C25F3/26 Primary

  of refractory metals · CPC title

• C25F3/16 Primary

  Polishing · CPC title