A new corrosion test for assessing flux residues is applied to marginally cleaned water soluble fluxed test boards and low solidsno clean fluxed test boards. This test method developed by Bono has been modified to accelerate the corrosion process. The corrosion mechanism observed in this study is conductive anodic filament CAF, a corrosion mechanism proposed in 1979 by Lando et al. It is postulated that this degradation mechanism is due to the high bias voltage 190 V coupled with the high humidity 85 and high temperature 85C conditions used in this test. Important parameters in the test method are discussed and recommended refinements are given.
Soldering & Surface Mount Technology – Emerald Publishing
Published: Feb 1, 1991