Use a flux agent and the right temperature to overcome these problems.
What Is Flux?
Oxides, on the other hand, need another approach.
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On iron, oxidation is commonly called rust.
However, oxidation affects tin, aluminum, copper, silver, and nearly every metal used in electronics.
Oxides make soldering more difficult or impossible, preventing a metallurgical bond with the solder.
Oxidization happens all of the time.
As with solder, there are several types of flux, each with key uses and some limitations.
However, additional flux is beneficial in some scenarios, such as surface-mount soldering and desoldering.
Rosin Flux
Some of the oldest types of flux are based on pine saprefined and purifiedcalled rosin.
Rosin flux is still used today, but modern rosin flux blends different fluxes to optimize its performance.
Rosin flux is acid when liquid.
When it cools, it becomes solid and inert.
It’s a good policy to remove rosin flux residue from a PCB.
Organic Acid Flux
One of the more common fluxes is water-soluble organic acid flux.
Common weak acids are used in organic acid flux, including citric, lactic, and stearic acids.
The weak organic acids are combined with solvents like isopropyl alcohol and water.
Organic acid fluxes are stronger than rosin fluxes and clean the oxides off more quickly.
It’s a blend of stronger acids like hydrochloric acid, zinc chloride, and ammonium chloride.
Inorganic acid fluxshould not be used for electronic assembly work or electrical work.
These fumes can lead to asthma and increased sensitivity to solder fumes.
Ensure adequate ventilation and, as necessary, use a respirator.
The greatest lead risk is the handling of the solder.
