IPC - Association Connecting Electronics Industries
Scope
This method covers the measurement of bow and twist by maximum vertical displacement of an unrestrained panel of either cut to size panels or finished rigid printed boards including single- and double-sided@ multilayer@ and the rigid segments of rigid flex printed circuits. This test method is only applicable to laminates greater than or equal to 0.5 mm [0.020 in] in thickness. This test method can also be used after etching or after thermal stress with requirements as agreed between user and vendor.