Sciencemadness Discussion Board

Electroplating Iron

dann2 - 8-8-2007 at 14:26

Hello,

Anyone done any Iron plating?
I attempted the following from US Pat. 3,850,701
_______________________________
Etched Ti.
Electro-deposition was carried out for 19 min in an electrolyte at 25C consisting of 130 g/l of ferrous sulfate (heptahydrate), 100 g/l of ammonium sulfate and 6 g/l of formalin by using said titanium plate as a cathode (a cathodic current density = 2.5 A/dm squared) and a low carbon steel as an anode.
_____________________________
Coating should be about 12 micron thick.

It did not work. I got a few streaks of Iron in Ti.
Perhaps stirring might help. The Iron Sulphate formed
hydroxide when dissolving so I will try acidifying water.

Dann2

Lambda - 8-8-2007 at 18:44

Hi @dann2,



Here are a few Books that may be of interest to you that can be downloaded via @Madhatter's FTP services in the Folder;



UPLOAD / Lambda / Electroplating /

as

ElectroPlating 101.pdf (4.7MB)

ElectroPlating - By Henry C. Reetz (H.H. Windsor 1911 - Republished by Lindsay Publications 1989) 99p - Revised and Up-To-Date by Popular Mechanics.pdf (21.5MB)

Workshop Practice Series # 11 - Electroplating - By J. A. Poyner (Argus Books - 1987 - Repr. 1991) 31s(d).pdf (4MB)

Vigor's Plating Guide (Grobet USA - 1999) 24s.pdf (12.3MB)

Furthermore, here are also a few Books and Patents on ElectroPlating. Chose FTP for the download, for then you may determine yourself in which format you want the files in.



http://www.archive.org/search.php?query=Electroplating

Enjoy !!

Lambda.

cathodic preparation of titanium

Rosco Bodine - 8-8-2007 at 23:53

There are cathodic etching / hydriding schemes which are applicable to plating of titanium and other metals .
It is possible to do this in a plating bath by first applying a low cathodic voltage to etch and hydride the metal ,
and then increasing the voltage to quickly deposit the metal plating so that a good metal to metal interface is produced .

Patents of possible interest concerning this technique are
US5368719 , US5456819 , US2801213 , US4153742 .

Pourbaix diagrams for titanium below were found here
http://www.engr.sjsu.edu/WofMatE/projects/srproject/srproj5....





[Edited on 9-8-2007 by Rosco Bodine]

chemist1066 - 21-8-2007 at 11:16

Go to a good library and look up some books on electroplating. There is Iron plating, however it is rare. If you are trying something at home, may I suggest trying Iron (II) sulfate with some citric acid.

dann2 - 30-9-2007 at 16:14

Thanks for replys guys,

I got back to the plating using my original formula. This time I stirred and kept the Ti brushed with a tooth brush. Got a good coating though there are still quite a lot of small pits (visible under microscope) in the coating. They do not go all the way down to the Ti though.
The original patent said the Ti was polished, I polished a piece of Ti using cardboard wheel and Cerium Oxide (polish) and coated. The Iron coat was easy to flake off. Bad idea, better to just etch in HCl.


Need to get my 900c (or so + steam in) oven going to convert to Magnetite and see if it stands up in a Chlorate cell.
If so it may be a better way to go than the Doped Tin Oxide precoat.

About the (wonderfully mysterious) Pourbaix diagrams.
Am I enterpreting the diagram correctly when I say that Ti will corrode in acid conditions when used as a Cathode (-ve approx 0 to -1.8 volts). Are the 'volts' as we see them applied are would they be measured with respect to some third electrode, like SCE.
?

Cheers,

Dann2

[Edited on 1-10-2007 by dann2]

[Edited on 1-10-2007 by dann2]

Rosco Bodine - 3-10-2007 at 05:55

Quote:
Originally posted by dann2

About the (wonderfully mysterious) Pourbaix diagrams.
Am I enterpreting the diagram correctly when I say that Ti will corrode in acid conditions when used as a Cathode (-ve approx 0 to -1.8 volts).


Correct . There is a window condition of mild cathodization potential where passivation is prevented , and still the potential has not yet reached the negative value required for hydrogen evolution blanketing or hydride formation .
In that window condition the bare metal is exposed to direct reaction , dissolution by acids , as well as ( I would expect ) to being plated by metals via "electroless" sorts of double decomposition reactions . This could also be exploited to secure metal to metal interfaces by schemes which rapidly transition the applied negative potential upon the exposed and unpassivated bare metal to a condition of being plated with other metals electrolytically , in preference to hydride formation as would occur otherwise in a bath which was simply acidic rather than being a salt solution of the metal to be plated .

Quote:

Are the 'volts' as we see them applied are would they be measured with respect to some third electrode, like SCE.
?

Cheers,

Dann2


The usual uncertainty would apply here as to any charts which fail to provide test cell description specifics , it is good only for showing relationships as a trend . You would need to derive your own multiplier as would apply to your own particular cell configuration for translation of what these values are in relation to your own cell . Gotta love that huh :P There's a lot of that in electrochemical charts .......
particularly where the test apparatus is not described for
the conditions under which the charted values were measured . Your results may vary according to the phases of the moon , astrological influences , ect . :P

BTW the Pourbaix diagram for iron is on the same page linked above where the diagrams for titanium were gotten .
Pourbaix is a funny name , and when I see it , I can't help wondering if the other children called him "poor boy" , or
"po beau" or something to that effect . :D

[Edited on 3-10-2007 by Rosco Bodine]

dann2 - 6-10-2007 at 06:25

Hello,

There is a Pourbaix Diagram for Lead Dixoide here in relation to sulphate ion:

http://www.geocities.com/CapeCanaveral/Campus/5361/chlorate/...

I have no idea if it is helpful to us.
The word 'Pourbaix' is pronounces as the sound that a duck makes when it is stepped on my a horse (or so I believe).
PAOR BAIXX
:D

Dann2

davetshave - 29-11-2007 at 07:32

I was wanting to look at those documents mentioned by Lambda. Can you provide some information on the location of Madhatters ftp server please?

conta6ion - 23-9-2011 at 12:27

The conditions are theoretical... but quite useful for modelling. The voltages you see are with reference to a standard hydrogen electrode (0.0V). If you are using something other than this your reference voltage will be different, and the voltage expectations need to be altered accordingly. Added to this is nearly always an overvoltage which is necessary to accommodate for whatever issues are not perfect within the plating cell. This includes things like concentration gradients and side reactions.

White Yeti - 23-9-2011 at 13:50

You can electroplate iron onto copper. The trick is that you have to electroplate reactive metals onto a less reactive substrate (relatively). So in this case copper works like a charm. But why do you want to electroplate iron? I'm just curious....
I'll post some pictures if you'd like.

dann2 - 25-9-2011 at 18:50


I was electroplating Titanium. The Iron was then turned into Magnetite for an Anode.

EmilyWatson - 1-12-2011 at 21:57

I have tried copper plating. Have anyone here done it before I would really like to share the theories. I connected the lid to the negative side of a 1.5 volt power supply and dipped into the blue vitriol .I used a length of copper tubing for my anode.

Power Supplies

[Edited on 2-12-2011 by EmilyWatson]

cyanureeves - 2-12-2011 at 18:18

great stuff lambda. thank you.