ALPHA 9230B is a halide-free, low-solid, no-clean flux. It is formulated for wave soldering of through-hole, mixed technology and surface mount assemblies. The flux is particularly effective when soldering in an inert atmosphere. The flux produces a tack-free surface with high surface insulation resistance and very little residue to interfere with electrical testing. The flux has been specifically formulated to resist degradation in surface insulation resistance and electromigration, even in situations where the flux does not experience soldering temperatures and when heavy levels of flux have been applied. The residues are non-corrosive and do not cause "greening" when in contact with copper or copper-bearing alloys. ALPHA 9230B is particularly well-suited for touch-up/rework situations where the application and processing of the flux is not always well-controlled.