Q: What is No-Clean Solder Paste
A: No-clean solder paste is a type of solder paste that contains a flux formulation designed to leave minimal residue after the soldering process. Solder paste is a mixture of tiny solder particles and flux used in surface mount technology (SMT) to attach components to printed circuit boards (PCBs). The flux in solder paste removes oxidation from the soldered surfaces, promotes good wetting, and helps create a robust and reliable solder joint.
“No-clean” solder paste is formulated to produce a residue that is not harmful to the components or the PCB and is intended to remain on the board without needing to be cleaned off after soldering. This can be particularly useful in situations where thorough cleaning might be difficult, time-consuming, or not recommended due to the components’ sensitivity or the circuit board’s design. The residue left by no-clean solder paste is typically non-corrosive and does not interfere with the functionality of the soldered connections. These are the reasons why they are often used on surface mount technology (SMT) assemblies.
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