Re: [MW:13207] MPI for the copper inclusion

Hi,

Hope, materials employed is not SS type 316/316L, in this case please conduct metallographic examination ( STD AS 2038 Intergranular Corrosion in Austenetic S.S) and perform PMI, Leaking samples could be observed through Dye penetrant method.

Copper in small amounts can cause cracking problems. While some companies use copper backing, it is usually in conjunction with mechanized welding systems where the welding parameters can be controlled to prevent melting the copper backing or allowing the arc to impinge directly against the copper.

If you were to have a problem with copper contamination, it would most likely be evident by very small cracks in the contaminated area. A dye penetrant test or fluorescent wet magnetic particle test with an AC yoke will provide a positive means of locating cracks caused by the copper or other means.

You could also polish the area of concern and etch the weld (root). If copper is present, it will be obvious once the area is etched. AWS B2.1 can be used as a source of information of the types of etchants to be used with different metals.

Regards

Manpreet Singh

From: rajeev arora <rajeevarora007@gmail.com>
Sent: Mon, 12 Dec 2011 22:00:46
To: materials-welding@googlegroups.com
Subject: [MW:13189] MPI for the copper inclusion
Dear Expert ,

Need your advice on the below matter ,

we are going the GMAW welding with copper backing , and found some copper pick up in the Root surface and check with the AUT and found no indication .

for the more clarification of the effect of the copper , we grind of the copper from the surface and check with the MPI and found some hire line indication and check with the LPT found NO indication.༯div>

I have one clarification , as we know that Copper is non magnetic material and during MPi if we checking and finding such indication it must be copper inclusion instead of crack because its not appearing.

Please advice if making any mistake.༯div>

--
Regards,

Rajeev Arora

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