Hi again Inge, I think we are talking about lifted lands or pads right? If so folks should check out IPC A600 . Beware of this slippery slope though. Gerry > Date: Thu, 14 Mar 2013 17:01:26 +0100 > From: [log in to unmask] > Subject: Re: [TN] IPC-6012 > To: [log in to unmask] > > I'm not sure what 'contractive' means as I only have British English > between my eyes, a weakness I have to live with. Mike may come to swing his > formidable tongue, or Brian Ellis. However, partially 'flitted' pads > sounds to me equal to future catastrophic failures. That you did not find > flitting in IPC-6012 does not mean that the failure category doesn't exist. > What is of most importance is what is required according to YOUR process > documents! That is something that is hammered into my Cortex Electronica > during many years at Ericsson. > > You mention nothing about your thermal stress conditions, so the gurus may > have some difficulty with doing a correct judgement. > > Inge > > On 13 March 2013 22:18, Vladimir Igoshev. PhD <[log in to unmask]>wrote: > > > I have a question for boards gurus, > > > > We run a set of tests to assess the workmanship of a PWB. The board > > had vias-in-pad (in essence PTHs overplated with Cu pads) under a BGA. > > > > After a thermal stress the pads were partially flitted due to cracked > > laminated underneath them. To me it's a recipe for disaster (like pad > > cratering after assembly). However, I saw nothing about it in > > IPC-6012. Did I just miss it? > > > > I'd really appreciate any contractive comments. > > > > -- > > Best regards, > > > > Vladimir Igoshev. PhD mailto: > > [log in to unmask] > > > > SENTEC Testing Laboratory Inc. > > 11 Canadian Road, Unit 7. > > Scarborough, ON M1R 5G1 > > Tel: (416) 899-1882 > > Fax: (905) 882-8812 > > www.sentec.ca > > > > ______________________________________________________________________ > > This email has been scanned by the Symantec Email Security.cloud service. > > For more information please contact helpdesk at x2960 or [log in to unmask] > > ______________________________________________________________________ > > > > > ______________________________________________________________________ > This email has been scanned by the Symantec Email Security.cloud service. > For more information please contact helpdesk at x2960 or [log in to unmask] > ______________________________________________________________________ ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________