Does no-clean flux need to be removed?

Short answer: not always, but often. Remove residues when:

• residues are conductive or ionic above spec,

• assemblies will operate in high humidity, salt air, or high voltage environments,

• components have low standoff or hidden terminations,

• conformal coating or potting will be applied and adhesion is critical.

Practical step: run IPC-TM-650 ionic tests and surface insulation resistance tests after process runs. ZESTRON’s labs can perform residue profiling.