Don't mate gold connectors with tin connectors?

[wwenze]

Connector Contacts: Gold, Silver and Tin | TvTechnology

One caveat: Don’t mate gold with tin as it is subject to fretting corrosion. As the connection is made, the tin tends to transfer to the gold pins, eventually forming a tin oxide layer on the gold. This layer can build up fairly quickly and because of the durable nature of the gold, is resistant to cracking and rubbing off.

So more googling:

Golden Rule No.12: Gold Contacts Should Not Be Mated To Tin Contacts 1, 8, 23
The gold-to-tin contact interface is susceptible to fretting corrosion. In addition to the normal fretting process, there is a related mechanism of transfer of tin to the gold interface which ultimately leads to a buildup of tin
oxide on the harder gold surface. Disruption of this oxide is more difficult
than for the case of tin oxide on tin.

http://www.te.com/documentation/whitepapers/pdf/aurulrep.pdf

Well that's written by Tyco / AMP so I better believe it.

 

[nigelwright7557]

Solder has so much tin in it so I cant see why there would be a problem.
People have been using gold plated components for many years.
I use B9A gold plated valve bases.

 

[bk856er]

Soldered connection is different I think. For plug in connections like Molex KK I try not to mingle metals and stick with one or the other, based on what I've heard from folks who work in the repair industry. Gold on gold OR tin on tin for me, if I have a choice and if it'll stay connected for a long time. Nice to see the technical explanation.


BK

 

[sonidos]

Way back in the 80's, when I worked at a computer manufacturer, we sourced various memory chips from the top makers (Micron, PNY, etc). It wasn't long that we heard about problems in the field with our computers and the engineers came back and told us no more tin leaded memory modules mating to gold connectors (or vice versa).

 

[nigelwright7557]

Some people pay extra for gold fingered pcb edge connections.
This would mean they cant use tin connectors.

 

[davidsrsb]

The OPs linked articles are saying that there is a wear problem when you mate and unmate repeatedly. Tin and gold low usage should be fine

 

[maesen]

Does anyone have experience with contact lubricants (as for example electrolube CG60) to prevent fretting corrosion with tin to tin connectors especially molex KK series?

 

[avtech]

I find DeOxit is very good for this type of application.

I use this at work on cannon plugs and rack mounted connections exposed to harsh environments with good success.

It is also good for cleaning up scratchy pots and switches.

 

[avtech]

Gold on gold OR tin on tin for me, if I have a choice and if it'll stay connected for a long time. Nice to see the technical explanation.

I found this article to be quite informative from SamTec.

 

[JonSnell Electronic]

Connector Contacts: Gold, Silver and Tin | TvTechnology



So more googling:


http://www.te.com/documentation/whitepapers/pdf/aurulrep.pdf

Well that's written by Tyco / AMP so I better believe it.

Does this mean that my Compaq Presario from 1982 will fail soon? It has gold flashed edge connectors and tin plated mating connectors. Better watch out if it is going to be unreliable. (Wonder if it is still under warranty for when the connections fail, must be a design fault).

 

[Galu]

In normal domestic conditions, I wouldn't fret about fretting!

PTFE lubricants are effective where repeated relative motion of the connectors is anticipated.