Flux is a core element of both paste and wire solders. Flux allows component leads to flow and moisten properly onto PCB pads. Flux particles can occasionally induce contamination or perhaps even electrical migration between component contacts (resulting in shorts) on the circuit board. High reliability systems - military, space and other fundamental ones - typically demand the cleaning of notable no-clean fluxes. PCB cleaning is frequently necessary for these kinds of circuit boards. Salespeople at Restronics New England have years of expertise in flux cleaning of all types... from high-volume batch cleaning machines to benchtop flux cleaning sprays and chemistry to eliminate flux residues. By analyzing the process in use and making appropriate recommendations for development, we can minimize the human labor necessary for hand spray cleaning and basically increase dependability and cleanliness by using a DI water based batch cleaner with aqueous chemistry.

Because the majority of US manufacturers produce high-reliability PCBs, flux cleaning is critical. Cleaning circuit boards with solvents, although very effective, can be highly hazardous for the environment and for humans. Organizations are shifting away from solvent-based cleaning and toward aqueous-based flux cleaning due to rising limits on the solvents used in vapor degreasers. Aqueous-based cleaners are usually zero-discharge, which indicates that no residue or wash solution is discharged; it stays in the equipment. Wash chemistry is often a blend of DI water and cleaning chemicals.

The suitable cleaning chemistry must fit the composition of the soils as part of PCB cleaning (could be flux residue, oils, or other contaminants). The majority of people try to use a basic alcohol cleaner but it typically leaves a white residue and doesn’t eliminate flux. This is especially difficult when customers need the PCB to be conformally coated. Usually, conformal coatings won’t adhere appropriately unless the PCB has been cleaned appropriately. All flux residues should be cleaned and verified using an Ionic Contamination tester before applying conformal coatings to military and space applications.