Hm.....struggling on this one! Has anyone, when conducting solderability testing using the wetting balance method experienced the following on alloy 42 leads. Leads pass the force / time criteria but subsequent testing up to x5 exhibit a strange phenomena Pass / Pass/ Pass / Pass / Pass Fail / Pass / Pass / Pass / Pass Pass / Fail / Fail / Pass / Fail Fail / Pass / Pass / Pass / Fail Pass / Pass / Fail / Pass / Pass As can be seen there is absolutely no pattern. I know testing is normally only carried out x1 but when determining the max force a lead is tested several times and the result is not what I would have expected, though my experience is typically with Cu leads. Is this indicative of alloy 42? If so what is actually happening? These parts are ASIC QFP's (gull wing) which are reflow soldered where quite a large # of joints are easily detachable by probing though the solder appears to form the basis of a good joint but with demarcation lines along the foot of the lead One last thing, when testing leads using an aggressive water soluble flux the pass / fail results appear no different. Any help / understanding would be appreciated! Regards, Iain. ******************************************************************** This email and any attachments are confidential to the intended recipient and may also be privileged. If you are not the intended recipient please delete it from your system and notify the sender. You should not copy it or use it for any purpose nor disclose or distribute its contents to any other person. ******************************************************************** --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------