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Acid Pickling Service
2

Acid Pickling Service

Acid Pickling Service

(OP)
Hi,

I am looking for a testing lab which can perform HF+HNO3 pickling test for metal coupons within the US. The project will properly compensate this testing for safely handling HF+HNO3 environment. Pleasse contact me if you are interested or I would appreciate if you can recommend me a testing lab.

Regards,

Paul

RE: Acid Pickling Service

If I understand your request that you want a lab to do immersion corrosion tests on metal samples using HF/HNO3 pickling mixtures.  

Is this for a potential material of construction screening test or a preexisting system?  

RE: Acid Pickling Service

Are you asking for the name of a company that will pickle some parts/coupons in HF + HNO3?  Testing labs do not perform this type of operation.  The types of companies that perform pickling specialize in surface treatment (cleaning, pickling, electroplating, etc.).  Please clarify the question and we will be able to assist you properly.  What state within the USA?

RE: Acid Pickling Service

(OP)
Thank you for responding. I need a testing Lab or surface treatment company to do immersion test with HF/HNO3 pickling environments for the purpose of screening metal parts application. The testing Lab or surface treatment company can be anywhere within US, preferred to be around New England area. I would appreciate if anyone can recommend a company name.

RE: Acid Pickling Service

Can you be a little more specific about you process and exactly what you are trying to accomplish.  With more information it may be possible to avoid spending a considerable sum.
  
The specific material, processing, thermal history, and others enter into the picture when it comes to acid pickling.

As you probably know HNO3/HF is very corrosive material to most metals so if you are looking to handle the mixture the variety of metals that have acceptable corrosion rates is very limited.

If you are looking for the effects on different materials by said mixture the problem is in determining the correct ratio of acids which varies greatly, depending on the material and expected result. There are labs that can recommend a process for pickling a specific processed material.

RE: Acid Pickling Service

(OP)
Unclesyd, thank you for the response. I am doing a project for specific application in the (5%HF + 10%HNO3) range pickling environment. I have modified coupons to be tested and would like to know a testing lab or company which can do the immersion tests. I would really appreciate if you can recommend a lab or a company. Thanks again.

RE: Acid Pickling Service

We are not a testing lab, but we pickle.  We pickle a lot of material.  I would be willing to pickle a set of coupons for you.  I could report the exact bath composition (it is checked a few times a week), temperature and time.
If this would work for you let me know.
Ed

= = = = = = = = = = = = = = = = = = = =
Corrosion, every where, all the time.
Manage it or it will manage you.
http://www.trent-tube.com/contact/Tech_Assist.cfm

RE: Acid Pickling Service

Comments:
1) Metal finishing jobshops that anodize aluminum castings or passivate stainless steel can do this. Maybe one of these: http://www.finishing.com/Shops/index3.html#newengland

2) If testing piping or tank materials, I think metals are a waste of money.  Try polyethylene for ambient temperature, natural polypropylene (no TiO2 filler) for up to 150oF, PVDF and PTFE for higher temperatures.

3) The 10%HNO3 + 5%HF concentration is a bit unusual; seems only really good for Si-containing aluminum.  It will excessively etch austenitic stainless, and etch + hydrogen embrittle ferritics, martensitics & titanium.  It is usual to maintain a HNO3:HF > 10:1 to avoid H embrittlement (HNO3 is an oxidizing acid, HF is a reducing acid).  
Purpose?  How was this concentration selected?
Also, if you or anyone else (perhaps EdStainless?) has a good etch inhibitor for this acid solution, please post.

4) Before testing, confirm the concentration units -- e.g., vol% of the concentrated acids [nitric acid (67 wt.%) and HF (49 wt%)] or absolute wt.%.

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