Calculation to determine PCB thickness

[Seth.T]

Hi,

In my design there are PCB boards. But i am worried the thickness of PCB will not be strong enough to withstand cracking and warp-age when under stress and strain.

Is there any formula i can use to calculate vibration on the PCB so i can increase thickness via mechanical ribs?


Please advise.
Seth

 

[Lok]

Hi Seth. Printed Circuit Boards (I suppose) are not structural members of usual build-ups, they are not usually designed to hold more than their own weight and as they vary a lot I doubt you will find a formula that works for your given details. More please.

For making weak flimsy PCBs stronger you can submerge it in epoxy resin (preferably a PCB certified one). Epoxy is a nice material with great mechanical properties a nice insulator and if chosen right a great thermal sink.

 

[wingman358]

As Lok said you probably shouldn't rely on the PCBs for structure. If there is vibration in the system, you might consider addressing the vibration rather than trying to strengthen the PCB. You could look at isolating the PCB through dampers or other methods.

Vibration of a part isn't necessarily bad, unless its at a resonant harmonic. Then things can break. Try looking into resonant frequency of a plate to get you started. Here's a brief intro for you: http://www.phy.davidson.edu/stuhome/derekk/resonance/pages/plates.htm

 

[Seth.T]

Good suggestions from you both, Lok and wingman,
I will look them up.

Thanks