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Need help with no-clean specs

Chrys

#14022

Need help with no-clean specs | 30 September, 1998

Hello, I've been evaluating a bunch of wave solder fluxes and found one that is absolutely perfect. I'm so excited I can't wait to switch over. Unfortunately, I have to assure reliability, and the only test I have in-house is ionic contamination (3.6 ug/in2 NaCl). I've got this data sheet with a bunch of specs on it, but no time to go looking up these specs. The only one I recognize is SIR. Can someone tell me what they all mean? Electromigration: Bellcore TR-NWT-000078 IPC high reliability class 3: IPC-SF-818 Copper Mirror Test: Modified J-STD; IPC Procedures Silver Chromate Paper: Bellcore; J-STD-004; IPC-SF-818 I'm sure that since the vendor says their product passes all these wonderful tests and complies with all these specs it means that this is a fine product. I just with I knew the technical translation. And should I go with this data or get some independent tests? One more thing - An engineer in another factory of ours asked me about electrocorrosion and interaction of water-based fluxes with soldermask. Hmm, another stumper for me. Any input from anyone would be welcome. Thank you in advance for you lesson in "Chemistry for Gearheads."

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Graham Naisbitt

#14023

Re: Need help with no-clean specs | 30 September, 1998

Chrys, Please, refer firsatly to J-STD-001 Appendix D. Now, consider: SIR testing will help define the reliability of your finished assembly - it will not tell you how clean it is. Which do you or your customer prefer? Present SIR testing defined under IPC-TM-650 and IPC-9201, request that you take one SIR reading per day over 7 days. BUT we/you can produce dendrites, or electrochemical reactions, within 20 minutes. Furthermore, zapping the test coupon with 50 volts will probably zap any dendrites without the right test equipment. Guess what, we have all this info and tons more. Rather than be zapped for spamming, please give me your address and other details, and I will send this info directly to you - including a report issued only a few weeks ago that proves the above. Regards, Graham Graham.Naisbitt@concoat.co.uk Hello, | | I've been evaluating a bunch of wave solder fluxes and found one that is absolutely perfect. I'm so excited I can't wait to switch over. Unfortunately, I have to assure reliability, and the only test I have in-house is ionic contamination (3.6 ug/in2 NaCl). I've got this data sheet with a bunch of specs on it, but no time to go looking up these specs. The only one I recognize is SIR. Can someone tell me what they all mean? | | Electromigration: Bellcore TR-NWT-000078 | IPC high reliability class 3: IPC-SF-818 | Copper Mirror Test: Modified J-STD; IPC Procedures | Silver Chromate Paper: Bellcore; J-STD-004; IPC-SF-818 | | I'm sure that since the vendor says their product passes all these wonderful tests and complies with all these specs it means that this is a fine product. I just with I knew the technical translation. | | And should I go with this data or get some independent tests? | | One more thing - An engineer in another factory of ours asked me about electrocorrosion and interaction of water-based fluxes with soldermask. Hmm, another stumper for me. | | Any input from anyone would be welcome. Thank you in advance for you lesson in "Chemistry for Gearheads." |

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