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Coating to prevent corrosion on hastelloy
2005
Is there a special treatment to prevent corrosion by sulfuric acid on a hastelloy probe?
Just a remark: This treatment or finishing, must not be anything that hardens, for there are flexible parts on the probe.
Thanks,
Diego Foltz HanserIndustrial Equipments - Sertaozinho, Sao Paulo, Brazil
publicly reply to Diego Foltz Hanser
Depending on the type of Hastelloy (you forgot to say) there might be options, but in general, this family of alloys are as corrosion resistant as can be any conventional coating. If plastics are out of the question I doubt you will find anything adecuate. Probably gold or platinum will prove somewhat effective but expensive.
Guillermo MarrufoMonterrey, NL, Mexico
2005
publicly reply to Guillermo Marrufo
2005
There is a "pickling" process for nickel alloys which is supposed to remove iron particles that may have been imbedded during the manufacturing processes.
1% Wt. HCl (20 Be)
1% Wt. ferric chloride
⇦ this on
eBay or
Amazon [affil links]
Water
Ambient temp.
Time is < 1hr.
Check result by immersion in 1% lab grade sodium chloride for 12-24 hrs. No red rust=success.
- San Jose
publicly reply to Bill Grayson
I use to coat the pressure sensors like the photo ones with two materials:
- PTFE also known as Teflon from DuPont (50 micrometers =2 mils)
- ECTFE known as HALAR from Solvay (300 microns = 12 mils)
The thickness of the coating is critical as you are coating a membrane.
- Spain
2005
publicly reply to Jordi Pujol
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