Process for the electrolytic polishing of a metallic substrate

Patent metadata

Field	Value
Publication number	US-2018171504-A1
Application number	US-201715842652-A
Country	US
Kind code	A1
Filing date	Dec 14, 2017
Priority date	Dec 21, 2016
Publication date	Jun 21, 2018
Grant date	—

Abstract

The present disclosure is directed a process for the electrolytic polishing of a metallic substrate, including the steps of (i) providing an electrolyte in an electrolytic cell having at least one electrode, (ii) disposing a metallic substrate as an anode in the electrolytic cell, (iii) applying a current at a voltage of 270 to 315 V from a power source between the at least one electrode and the metallic substrate, and (iv) immersing the metallic substrate in the electrolyte, wherein the electrolyte includes at least one acid compound, at least one fluoride compound, and at least one complexing agent.

First claim

What is claimed is:

1 . A process for the electrolytic polishing of a metallic substrate, comprising the steps of:
providing an electrolyte in an electrolytic cell comprising at least one electrode; disposing a metallic substrate as an anode in the electrolytic cell; applying a current at a voltage of 270 to 315 volts from a power source between the at least one electrode and the metallic substrate; and immersing the metallic substrate in the electrolyte; wherein the electrolyte comprises at least one acid compound, at least one fluoride compound, and at least one complexing agent.

2 . The process according to claim 1 , wherein the current is applied at a voltage of 285 to 305 volts.

3 . The process according to claim 1 , wherein the electrolyte has a temperature in the range of 10 to 95° C.

4 . The process according to claim 1 , wherein the current is applied at a current density in the range of 0.05 to 10 A/cm 2 .

5 . The process according to claim 1 , wherein the current is applied for a time in the range of 1 to 240 min.

6 . The process according to claim 1 , wherein the metallic substrate is selected from the group consisting of Ti-6Al-4V, Inconel 718, Invar and combinations thereof.

7 . The process according to claim 1 , wherein the electrolyte further comprises at least one medium.

8 . The process according to claim 7 , wherein the electrolyte further comprises additives.

9 . The process according to claim 1 , wherein the at least one acid compound is in an amount of not more than 20 wt.-%, and/or the at least one fluoride compound is in an amount of not more than 40 wt.-%, and/or the at least one complexing agent is in an amount of not more than 30 wt.-%, based on the weight of the electrolyte.

10 . The process according to claim 7 , wherein the at least one medium is in an amount of at least 10 wt.-%, and/or additives are in an amount of not more than 25 wt.-%, based on the weight of the electrolyte.

11 . The process according to claim 1 , wherein the at least one acid compound is selected from the group consisting of inorganic or organic acids such as sulfuric acid, nitric acid, phosphoric acid, hydrochloric acid, formic acid, acetic acid propionic acid, or mixtures thereof, preferably is selected from the group consisting of sulfuric acid, nitric acid, phosphoric acid, or mixtures thereof, more preferably is sulfuric acid.

12 . The process according to claim 1 , wherein the at least one fluoride compound is selected from the group consisting of ammonium fluoride, sodium fluoride, potassium fluoride, magnesium fluoride, calcium fluoride, trifluoracetic acid, or mixtures thereof, preferably is selected from the group consisting of ammonium fluoride, sodium fluoride, potassium fluoride, magnesium fluoride, calcium fluoride, or mixtures thereof, more preferably is ammonium fluoride.

13 . The process according to claim 1 , wherein the at least one complexing agent is selected from the group consisting of methylglycinediacetic acid (MGDA), ethylenediaminetetraacetate (EDTA), diethylenetriaminepentakismethylenephosphonic acid (DTPMP), aminopolycarboxylic acids (APC), diethylenetriaminepentaacetate (DTPA), nitrilotriacetate (NTA), triphosphate, 1,4,7,10 tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), phosphonate, gluconic acid, f3 alaninediactetic acid (ADA), N-bis[2-(1,2 dicarboxy-ethoxy)ethyl]glycine (BCA5), N-bis[2-(1,2-dicarboxyethoxy)ethyl]aspatic acid (BCA6), tetracis(2-hydroxypropyl)ethylenediamine (THPED), N-(hydroxyethyl)-ethylenediaminetriacetic acid (HEDTA) or mixtures thereof.

Assignees

• Airbus Defence & Space Gmbh

Inventors

• Bagehorn Sarah
• Mertens Tobias

Classifications

• C25F3/24

  of iron or steel · CPC title

• C25F3/18 Primary

  of light metals · CPC title

• C25F3/26 Primary

  of refractory metals · CPC title

• C25F7/00

  Constructional parts, or assemblies thereof, of cells for electrolytic removal of material from objects (for both electrolytic coating and removal C25D); Servicing or operating · CPC title

• C25F3/16 Primary

  Polishing · CPC title