Inconel 625 Plus 1

[WeldGk]

I have been required to compare the corrosion resistance of Inconel 625Plus to Inconel 725 for seawater applications (from -20F to 250F) NACE MR0175 does not provide any comparison data, it only states that these materials are suitable for chloride resistance. Does anyone know of a good source for this information?

 

[SnTMan]

Inco?

Regards,

Mike

 

[EdStainless]

Don't the two chemistries actually overlap?
Either way it will be slightly worse than for 625. The age hardening will have a negative effect on corrosion resistance.

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Still trying to help you stop corrosion.
formerly Trent Tube, now Plymouth Tube
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[SJones]

ISO 15156/NACE MR0175 is not applicable to seawater exposures (unless H2S is being passed through it). The best source of data will be the Special Metals web site and the specific materials datasheets plus the guide to aqueous corrosion manual that can be downloaded. Another good source is the NACE COR-SUR database.

Steve Jones
Materials & Corrosion Engineer

http://www.pdo.co.om/pdo/

 

[TVP]

Here are the links that the others mentioned:

http://www.specialmetals.com/marine.php

http://www.specialmetals.com/technical.php

http://www.specialmetals.com/documents/SM Aqueous Corrosion Book.pdf

 

[mshimko]

Most sources will list the corrosion resistence of both materials as "excellent", "immune", or something similar.

I also know that under extremely tight crevices 625 can be susceptible to crevice corrosion.

Is there a specific concern someone is lookig into?

 

[shineystar]

Special Metals don't actually produce a Inconel 625plus.

Alloy 625 plus is the exact equivalent grade of material to Special Metals Inconel 725.(chemistry, mech props etc)

There is a difference between Alloy 625 and Alloy 625plus.

Carpenter used to manufacture 625plus and I understand that Foroni Spa now manufacture the alloy under licence.

If you contact Foroni Metals in the UK or one of thier distributors for this grade, then they'll be able to forward you relevant data sheet for 625plus

 

[EdStainless]

Allegheny Ludlum also makes 625 Plus.

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Still trying to help you stop corrosion.
formerly Trent Tube, now Plymouth Tube
eblessman@plymouth.com
or edstainless@earthlink.net