Hi Christopher, There is no standard. The 'red flag' amount is 4 wt%. However, if the AuSn-IMCs are not uniformally distributed but concentrated near one interface or the other, 'brittle' failures can occur at smaller overall weight %'s because of the localized concentration. Werner ************************************** AOL now offers free email to everyone. Find out more about what's free from AOL at http://www.aol.com. --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 -----------------------------------------------------