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Q. Sir,
As I joined newly a chrome plant,
Please provide me the link or something by which I can check concentration of Cr2O4 and H2SO4, and how to set current density in bath, and maintain smooth working of process.

Anil Chauhan
Employee - Dammam, Saudi Arabia
June 4, 2022

⇩ Closely related postings, oldest first ⇩


- PATERSON New Jersey

simultaneous replies

"Chromium Plating"
by Weiner & Walmsley

on AbeBooks
** rarely available **

or Amazon
** rarely available **

(affil links)

A. Hi Tom. Most often comes the problem with hazy chromium deposit before you plate chromium on the part. Have you controlled pH-range in nickel solution if it to high or the brightener.

How are your rinses after nickel solution, maybe they are full with contamination and what pH-range. You can also try to activation the part in 5 percent sulfuric acid and a clean rinse before you plate chromium.

How did you start the current in the chromium. How is your rack did they lose connection. Have you controlled direct current characteristic maybe you have some alternating current or ripple. I hope this ideas give you some answer. Regard Anders S

Anders Sundman
Anders Sundman
4th Generation Surface Engineering
Consultant - Arvika,


A. Normally it is too many amps per sq inch for the temperature.

Try raising the tank temp 5 °F and see if most of it does not go away.

If that is not viable, try lowering your amperage for a given load by 10%. Is your tank temp uniform, no stratification or cold spots? It is rare, but it can haze from too few amps for the temperature.

James Watts
- Navarre, Florida

A. Tom,

I work in a Plating Department we Plate Nickel and Chrome on Grocery Carts,

We use TriValent Chrome for our chrome and have had the haze you speak of not sure if it is same haze, The haze I had was from High Chrome Regulator in the Chrome Tank to take care of this you can add a couple scoops of Activated Carbon it is a Black Powder,If this is not the problem the Carbon will not hurt anything at all carbon helps take care of the metals that are suspended in solution.

I work 3rd shift on in the Plating Department as A supervisor I have 2 years experience with Plating and chemistry. Thanks.

Bob Nichols
- Richmond,Virginia





Varun Bhalla
- Delhi, (INDIA)


I would mention two things which other have not mentioned here, may be they will be helpful to you to avoid haze. Try 2-5 grams per liter of chromic acid pre dip just before the chrome plating bath.

Second, try to see if your water rinses after (if you nickel plate) nickel plate are too cold. If so, try a bit warmer water in these rinses. Hope it will work. Nice to see responses here from as far as India. I think I know Mr. Varun Bhalla ... World is shrinking, is not it?   :-)

Hemant Kumar
Hemant Kumar
- Florida, USA

A. Many of the other replies are suggesting the problem as passive nickel which generally gives a strong stainy haze. A very light haze can come from high fluoride in the chrome bath, common in some of the earlier SRHS baths.

Geoffrey Whitelaw
Geoffrey Whitelaw
- Port Melbourne, Australia


Q. Hi,

I need some information regarding hard chromium plating. Is it usual to sparge air in the plating tank? If yes, what is it for - for removing heat or for agitation? Or on the other hand for typical plating loads, is the tank needed to be heated with a heater to maintain the temperature?

Susheel Yadav
University of Cincinnati - Cincinnati Ohio

A. Is air agitation in chrome common? -- some use it and others do not. Why? -- to get improved solution flow across the part, to equalize temperature and to maintain uniformity of the chemicals.

Is it needed? -- Not really, a proper loading of the tank and amount of amperage will provide enough outgassing to give a good chemical movement across the part and thus mixing. Downside is it brings a lot of the sludge off of the bottom of the tank which causes particles becoming embedded in the plate and frequently treeing.

You need heat to bring the tank up to temperature initially and if you have a heavy tank loading, you need cooling after that. Normally you would not need ongoing heat as chrome plating is very inefficient and generates lots of heat.

James Watts
- Navarre, Florida

A. I don't have your haze problem, but if your chromium activation solution is too old (I mean the conductivity is too little) in the low current density areas you can see some hazy deposits.

kerem topcu
- Boz¸y¸k, TURKEY

A. Hi Tom,
There are many reasons for haze.
As I have observed, temperature plays an important role. After that the ratio and amount of sulphate -- if the sulphate ratio is low then haze starts for chrome plating which does not get clear during buffing. We lastly observe the current -- sudden supply of current creates haze during chrome plating.

- Delhi, India

August 29, 2014

A. Tom,

if parts come out cloudy after chrome plate, check chrome ratio, check the nickel brightener is not loaded too much, fallen parts in nickel or chrome tank touching with your plating rack parts. Other possibility passivation nickel surface.

popat patel
Popatbhai B. Patel
electroplating consultant - Roseville, Michigan

Multiple threads were merged: please forgive repetition, chronology errors, or disrespect towards other postings [they weren't on the same page] :-)

Q. What major defects generally develop in Hard Chrome Plating?
Reason for such defects and how to avoid the defects?
For better adhesion what is added?
Any Brightening agent for Hard Chrome Plating Please advise.

Karnail Singh
learning the process - New Delhi
August 5, 2008

"Hard Chromium plating"
by Robert K. Guffie

on AbeBooks

or Amazon

(affil links)

A. The answers to 1 and 2 will fill a book.
For better adhesion, you add nothing! you do a better job in the prep steps and maintain your chrome tank within specifications.
Hard chrome is very bright if the substrate is smooth and if you are using the correct amperage per square inch for the temperature of the solution. There is a window that is bright and outside of that it is burned or cloudy or milky. PS it is not "hard chrome" if it any of those. It will be much softer!
You would be well off to buy a book that is listed at this site's book list.

James Watts
- Navarre, Florida
August 6, 2008

September 4, 2008

A. Dear sir,
The problem may be with improper cleaning.Review cleaning methods and check degreasing solutions to make sure that they are efficient.And check the operating temperature, at 55-60 °C temp it works better.The chromic acid concentration should be at 250 gms/ltr and sulphates 1.8-2.25 gms/ltr.

Shoban Kesarapu
Shoban Kesarapu
plating chemicals supplier - Secunderabad, A.P., India

October 17, 2008

I don't claim I understand, but Lowenheim [adv: this book on AbeBooks, eBay, Amazon] has a good chapter. Let me at least try to help this gentleman in India from book experience and from theses and papers:

1/ poor throwing power, plates more on ends and edges.
2/ cracks in the plating.
1/ adhesion is automatic from chromic cleaning
2/ easy to maintain bath
1/ formation of oxygen AND hydrogen gas bubbles.
2/ carcinogen

Anode issues:
1/ chromating like sulphating of battery and needs cleaning of Pb anodes. solution: use 10% silver anode.

I hope someone can add more.

The ratio of catalyst is very important. The temperature control is very important. If you have XRD, you can follow the crystal structure.

Yannoush Greek
- Greece

Q. Hi -- I have problem with cloudy and milky deposit in decorative chromium plating. This problem occurs in all the pieces, especially low current density. Meanwhile baumé of the chrome bath is 22 and the temperature is 40 °C.

elham bolouri
teacher and base - mashhad,iran
July 10, 2014

July 22, 2014

A. Hi Elham,

Possible causes are:

1. Too high pH (>3).
2. Too high plating solution surface tension (low wetting agent).
3. Too low chromium concentration.
4. Metallic impurities (e.g., Zn, Pb).
5. Poor nickel activation prior chromium plating.
6. Plating part dries off prior chromium plating.


David Shiu
David Shiu
- Singapore

July 31, 2014

A. I'll add two other possible causes of problems: catalyst too high/low, and chloride contamination. The latter is common in shops that try to cheap out on the rinse following the nickel plating step. There is no way, that I know of, to remove it.

The former problem can be evaluated via Hull Cell or chemical analysis for sulphate and/or fluoride.

dave wichern
Dave Wichern
Consultant - The Bronx, New York

A. Silver nitrate will precipitate and remove chloride from chrome plating solutions.

jeffrey holmes
Jeffrey Holmes, CEF
Spartanburg, South Carolina
August 4, 2014

Q. How can I remove chloride in chrome tank? I know silver nitrate can, but it is expensive. Can you help me?

elham bolouri [returning]
- mashhad.iran
August 29, 2014

A. Hi Elham. Letter 56140 "Determining and removing chloride in Chrome plating solution" describes a method to dummy it out at high temperature and high current density.


Ted Mooney,
Ted Mooney, P.E.
Striving to live Aloha - Pine Beach, New Jersey
August 2014

A. I would like to add one more item to the excellent answers have received so far. Any parts on the bottom of the plating tank can also cause this problem.

Lyle Kirman
consultant - Cleveland Heights, Ohio
August 1, 2014

A. If the bath chemistry is correct, milky deposit is almost always by too low a current density for the temperature of the solution.

James Watts
- Navarre, Florida
August 6, 2014

thumbs up signHi. Thanks for suggestions especially David Shiu. I used your suggestion and corrected the chrome tank.

ELHAM BOLOURI [returning]
- mashhad.iran
August 25, 2014

Nickel blows in bright chrome finishing

Q. I refurbish classic car windscreens and quarterlights
I have just received a batch from the platers where around the screw holes and edges are not covered in chrome and are showing the brownish nickel underneath.
How do I fix the problem?

David James
restorer - Lichfield, Staffs, UK
January 25, 2015

A. Hi David. Unfortunately, you must send them back to the same or a different plating shop for replating. There is no way to repair the missing chrome.


Ted Mooney,
Ted Mooney, P.E.
Striving to live Aloha - Pine Beach, New Jersey
January 2015

A. May be due to low sulphate or low temperature.

Gulshan Sachdeva
- Ludhiana, Punjab India
April 10, 2015

July 28, 2015

A. Hi David,

You have to strip the chrome, and plug all holes on part, and rechrome all parts. Strip chrome - rinse - activate Ni surface - chrome predip - then chrome the parts (and check your chrome tank chemistry).

popat patel
Popatbhai B. Patel
electroplating consultant - Roseville, Michigan

Q. Hi.
I have a big problem with chrome plating. In our company, we plated brass parts with nickel and chromium. But after chrome plating, parts have been cloudy and opaque. In addition, we recently had a bath chrome return. After this the pieces in the middle of a high opacity. Please guide me.

elham bolouri [returning]
- mashhad.iran
December 15, 2015

A. The most common cause of cloudy chrome plate is the wrong current density for the bath. Assuming a common chrome/sulphate bath, then the temperature is probably too low for the current density applied.

James Watts
- Navarre, Florida
December 15, 2015

Q. Hi. I am not able to achieve proper thickness levels in bright chrome plating. I have added barium carbonate in defined quantities to reduce sulphate content. Can anyone guide me through this?

J.R POLYPACKS - Hsp,Punjab, India
May 9, 2018

May 2018

"The Canning Handbook of Surface Finishing Technology"

on AbeBooks

or eBay or


(affil links)

A. Hi cousin Prabh. The Canning Handbook lists the number one cause of little or no chrome deposit as nickel plating which has grown passive. The same handbook suggests the number one reason for adding barium carbonate is to correct poor throwing power.

Unfortunately, we probably need much more data to guide you through.

Are you an experienced chrome plater and this new problem appeared on parts you previously plated successfully? Was it sudden or gradual? What was the ratio before and after your barium carbonate additions. Is this a new part, perhaps requiring greater throwing power? Details please! Thanks!


pic of Ted Mooney
Ted Mooney, P.E. RET
Striving to live Aloha - Pine Beach, New Jersey

Please, most of our jobs are getting only partial chroming -- sometimes completely burned black colour surface.


We have checked density and all but still getting issues. Why the job is getting complete black colour? Our tank is an ardi art tank.

Jinto joy
Chrome engineer - Lagos
September 16, 2021

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