ALPHA® Liquid Soldering Flux

ALPHA® EF-Series fluxes offer environmentally friendly benefits, while providing unmatched soldering performance. The ALPHA soldering flux line is unsurpassed in providing wave soldering process solutions. Its alcohol-based fluxes provide excellent wetting, virtually defect-free soldering and high line throughput across the full range of applications.

Our latest line of wave solder fluxes, including our EF-Series, is designed to provide the highest level of performance and reliability in its class. Specific wave solder flux products were formulated to offer a safer and more environmentally friendly alternative to ordinary fluxes.

Alpha fluxes have been developed using the latest Alpha flux technology. We operate many Liquid Soldering flux production facilities around the world, and each of these sites follows strict standards that assure high product quality and unmatched consistency.

Selective solder guide image

 Alpha Selective Soldering Guide



Product Technology Solids Content Electrical Reliability Best Used On Assembly Types Halide Free Pin Testability







Bellcore SIR



EF-2210 Rosin-Free No-Clean Low X     X   II,III X High
NR-330 Low X     X   II,III X High
WS-3355 VF Water Soluble High X         II,III,IV   High*
WS-375 High X         II,III,IV   High*
EF-5601 Rosin-Containing No-Clean Low X   X     I,II X Moderate

Rosin-Free No-Clean

Low X         II,III X Very Good
SLS-65C Low X     X   II,III X Very Good
NR-205 Rosin-Containing No-Clean Low X     X   I,II,III X Very Good
EF-6100 Low X   X X   I,II,III X Very Good
RF-800 Low X X   X   II,III X Moderate
EF-6850HF Low X X X X   II,III X Moderate
EF-6103 Low X   X X   I,II,III X Moderate
EF-8000 Med X   X X   II,III,IV X Moderate
EF-8300 Med X     X   I,II,III X Moderate
EF-9301 Med X   X X   I,II,III   Moderate
615-25 Series High X X X X X I,II,III   Low
EF-12000 High X   X X X I,II    Low
EF-8800HF High X X X X   II,III,IV X Moderate
WS-857 Water-Soluble High X* X* X* X*   II,III,IV   High*
WS-870-25 High X*         II,III,IV   High*
 Assembly Type
Simple, single sided, FR2 / CEM-1 laminates
Dual sided FR-4 w/ PTH's, 1.6mm thick, up to 4 inner copper layers, metallized pad finishes
Complex, up to 12 inner copper layers, OSP pad finishes, all processing in air
>2.4mm thick, >12 inner copper layers, large high heat capacity components


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