Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Intermetallic Compounds

Views: 5808

#78896

Intermetallic Compounds | 18 September, 2017

IS there an IPC standard or equivalent which specifies the maximum thickness of intermetallic compounds (IMC) in a reliable solder joint?

reply »

#78914

Intermetallic Compounds | 21 September, 2017

There is no standard minimum / maximum IMC thickness.

* There needs to be an IMC

* Thinner IMCs are preferred over thicker IMCs

reply »

#79229

Intermetallic Compounds | 24 October, 2017

As far as I know there is no standard thickness minimum or maximum thickness. It depends

reply »


Jan

#79433

Intermetallic Compounds | 5 December, 2017

You find good information in IPC-4554 that includes recommended total Sn thickness and recommended free Sn. It refers to how much usable Sn is needed to meet coating durability categories defined in J-STD-003. As example, if you need 6 months shelf life you should have a minimum of 0,6 microns useable Sn. If you on top of that shall expose the boards to 3 times reflow i would recommend 0,8 micron usable tin. This means the supplier should have a plating thickness process target of minimum 1.15 micron as it is written in the standard.

reply »

convection smt reflow ovens

ICT Total SMT line Provider