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what is the cause of green decay on the soldered wires

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arnold

#38261

what is the cause of green decay on the soldered wires | 7 December, 2005

were having a problem on the units after soldered. after few hours or days the soldered wires has green decay. what does it cause. how can i prevent this.

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#38264

what is the cause of green decay on the soldered wires | 7 December, 2005

We need more information about the situation. For instance: * Describe the green residue * Talk about the distribution of the problem, including a single lot or from various lots and over components and component types on the board * Tell us about the board (ie, thickness, type, solder mask, pads coating, pad size, etc) * Describe the component(s) (ie, type, termination finish, etc) * Take us through your process steps that proceed the problem, including the reflow profile and its control * Help us with the solder and the flux you are using

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RDR

#38266

what is the cause of green decay on the soldered wires | 7 December, 2005

Would you by chance be soldering copper to aluminum?

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PWH

#38270

what is the cause of green decay on the soldered wires | 7 December, 2005

I have seen problems similar to this caused by too high concentration of cleaning solution used in ultra-sonic cleaning process. If cleaning solution is used, make sure it is compatible with solder process. Also, improper mixing of fluxes and solder or use of the wrong solder/flux (ex. no-clean instead of water sol.) might be someting for you to investigate.

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#38289

what is the cause of green decay on the soldered wires | 8 December, 2005

Hi,

Copper oxide is green right? So the green residue after a few days is corrosion of the wire?

Regards,

Grant

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KEN

#38315

what is the cause of green decay on the soldered wires | 8 December, 2005

Is this a wire dip tinning process?

If yes, then your flux is probably trapped under the insulator, causing corrosion. BAD BAD BAD (hopefully you don't make wire harnesses for air planes or passenger trains).

More info please.

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#38321

what is the cause of green decay on the soldered wires | 8 December, 2005

Grant

Copper Oxide [Cu2O]: Color is red to a deep red that can appear almost black. Luster is adamantine or submetallic to dull or earthy if massive. Transparency: Crystals are transparent to translucent. Look here: http://mineral.galleries.com/minerals/oxides/cuprite/cuprite.htm

Copper salts are green.

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#38363

what is the cause of green decay on the soldered wires | 10 December, 2005

I have seen a similar problem once about 15 yrs ago. Someone decided to try a water wash flux for tinning wires. Bad idea! The wires were dipped in the flux, then in a solder pot. As the lead tin's it forces the flux in the strands to move up the wire. Much flux goes up under the insulation. I dont think washing would help much for this particular application but in this case they were not washed anyway. The wires truned green in a few days. They were coroded all the way through in a month or so. As in-the wires were falling off the boards. If this is the problem you have, you need to re-call any product that was shipped.

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arnold

#38695

what is the cause of green decay on the soldered wires | 26 December, 2005

is there any term called on that corrosion or green contamination?

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Slaine

#38763

what is the cause of green decay on the soldered wires | 3 January, 2006

on church copper roofs they call the green stuff verdigree (dont know if ive spelt it right)

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#38766

what is the cause of green decay on the soldered wires | 3 January, 2006

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