Gold porosity testing was initiated to detect the potential of metallic migration (copper migration). In the event of the copper migrating through the coating metals (nickel/gold), it would oxidize/corrode on the contact surface and create an intermittence/open from from the tab area to the connector. Initially, it was done with a nitric bell jar test, but since has evolved to an electrolytic type test. Details of the testing may be obtained from IPC-TM-650 and related IPC documents. BellCore also has some extensive documentation for Porosity. I hope this helps, If you need more data, Email Me. JOHN -----Original Message----- From: Pratap Singh <[log in to unmask]> To: [log in to unmask] <[log in to unmask]> Date: Sunday, March 29, 1998 3:02 PM Subject: Re: [TN] Gold Porosity >Kelly Kovalovsky wrote: >> >> I am looking for some information on gold porosity as it applies to common PCB >> edge tab connector contacts. More to the point, I would like to know: >> >> What is a good working definition of porosity? >> What is the common test(s) for porosity and the theory behind the test? >> What are the common causes for test failure? >> >> Kelly Kovalovsky >> >> ################################################################ >> TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c >> ################################################################ >> To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: >> To subscribe: SUBSCRIBE TechNet <your full name> >> To unsubscribe: SIGNOFF TechNet >> ################################################################ >> Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. >> For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 >> ################################################################ >Kelly, IBM specs define gold porosity very well and have three test >methods to test for gold porosity, GEL, Electrographic Paper and nitric >acid vapor method. > >I have retired from IBM and have no direct access to specifications but >you should be able to serach on the internal search facility. > >American Electroplaters' Society has several documents that talks about >nature, cause and effect of the porosity in electrodeposits. Also look >into plating magazine December 1969 article by A.A. khan " Porosity >Testing Techniques in Gold deposits", very informative. > >By the way at which IBM site you are working? Let me know if you need >further help. > >################################################################ >TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c >################################################################ >To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: >To subscribe: SUBSCRIBE TechNet <your full name> >To unsubscribe: SIGNOFF TechNet >################################################################ >Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. >For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 >################################################################ > ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################