-- The Home Page of the Finishing Industry
23+ years of serious education, promoting Aloha,
& the most fun you can have in metal finishing smiley
    no popups, no spam
on this site
current topics
topic 28753

Stripping Tungsten Carbide thermal spray coatings from 300M steel

Metalx nickel stripper
... plus Cufix E Copper Stripper, TN-64 TiN Stripper
& Strippers for Tungsten Carbide in Cobalt Matrix

A discussion started in 2004 but continuing through 2017


Q. We have a need to strip a tungsten carbide HVOF thermal spray coating (Diamalloy 2005) from a 300M alloy steel components. Somebody said citric acid will do this. Any advice from out there?

Thanks in advance for your help.

Richard H [last name deleted for privacy by Editor]
Aerospace sheet metal, welding & thermal spray - Blainville, QC, Canada


A. Since you are Aerospace, you must follow the overhaul/repair manual of the OEM or get an approval for an alternate method (which can be lengthy and tough to come by). If you do not use the approved methods, and a part fails, just the law suit (lawyer cost) would break many companies. The downside of this type of individual effort is massive.

James Watts
- Navarre, Florida


Don't assume, James Watts, that the person asking an honest question is less knowledgeable than yourself. Dick knows a thing or two about "aerospace".

Jason Sakalauski, EIT
- Winnipeg, Manitoba, Canada


thumbs up sign James certainly meant no disrespect, Jason, whereas to assume that strangers know things is very dangerous! James has warned a half-dozen people here who wanted to install chrome plating facilities in their garage/basement about the safety & environmental issues -- should he have assumed that they are no less knowledgeable than himself, and just stuck to the mechanicals of how to do it?

We ask people to read our simple guidelines before posting, and ceaselessly beg them to introduce themselves and their full situation, and not leave out the context. Among other things, it prevents such unintended slights, followed by people exacerbating the situation by insulting our helpful responders.

Ted Mooney, Teds signature
Ted Mooney, P.E.
Pine Beach, New Jersey


A. Nitric acid may not do the job as the Nital Etch process used nitric acid and nital etching is used on HVOF layers to verify NO burning as result of grinding.
What we have done to remove the HVOF is just grind it off with the same grinding stones as used to grind the HVOF layer initially to it's roughness requirements. due to the hardness of HVOF coatings, these are special grinding stones.

I hope this is of help.

Bakker Sven


Q. Nital etch inspection on PH 13-8 Mo and 17-4 PH steel. Is the Nital etch inspection on precipitation hardening steels effective? is there any influence from burning marks (grinding) on the outside diameter like on carbon steel heat treated products?

Peter Aarts
Aerospace - Geldrop, Holland

January 14, 2013

Q. I need to remove chromium carbide coating from steel sample using any chemical methods without causing changes to the substrate. Thickness of coating is 20µ. Does anyone have information about it? Thanks.

Elena Sparrow
- Moscow, Russia

January 31, 2013

A. Ultrasonically pulsed waterjet technology will remove hardcoating such as Chrome and HVOF using normal tap water without causing damage to the substrate.

Jeff Shaffer
Pratt & Whitney PurePulse Technology - San Antonio, Texas, USA

March 31, 2013 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Q. Dear Sir,

The problem is stripping of chrome carbide embedded on steel substrate. It is not going with HF and caustic-peroxide mixture. Can you suggest to me some other strippers?

Ramasubramanian Sankara Bhatter [returning]
- Bangalore, Karnataka, India

Stripping Tungsten Carbide from I.D housing

October 26, 2017

Q. Stripping Tungsten Carbide from I.D housing what methods can be used.

Any suggestions would be greatly appreciated.

Sashi Kumar
- Edmonton, Alberta, Canada

October 2017

? Hi Sashi. Your housing is made of 300M steel, or something else? What is the length and diameter of this I.D.? Is it open on both ends, or a blind hole? It's not clear to me what is inapplicable about the earlier suggestions ... can you comment on them please? Thanks.


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

This public forum has 60,000 threads. If you have a question in mind which seems off topic to this thread, you might prefer to Search the Site

ADD a Comment to THIS thread START a NEW threadView CURRENT TOPICS

Disclaimer: It's not possible to diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental ComplianceTesting Svcs. & Devices

©1995-2018, Inc., Pine Beach, NJ   -   About   -  Privacy Policy
How Google uses data when you visit this site.