Due to a process change in PCBA production the flux dispenser was not consistent in flux spraying at the positions undergoing selective wave soldering. When performing a simple Residues RAT test a clear red coloration was seen. It is indicating…

It is typical to see flux residues when performing through hole mounting of component pins. The question is whether the residues are harmful to the electronics functionality. If the flux residue is exposed to high temperature and humidity it can…

The residues after soldering depends on the flux system used and the soldering temperature profile used. The images of acids used in solder flux show how heating will deactivate the acid parts. The acid is placed in petri-dishes and the…

Contamination with active organic acid, as can be found in unreacted flux residues has been reported to increase silver sulphide formation rate and amount. Environmental conditions such as humidity, temperature, contamination and gases affect the reliability and lifetime of electronic…

Residues RAT was used to investigate a standard procedure for cleaning flux residues. Hand soldering was performed in three places on two similar PCBA´s, one of which a consequent cleaning procedure was done. Then both PCBA’s were tested with Residues…

Rework of components increases the risk of unreacted flux residues to be left on the surface of PCBAs. The main issue here is whether this rework procedure results in a reliable product. Therefore it is important 1) to know the…