Wave soldering is a manufacturing process used to solder electronic components to a printed circuit board (PCB). It is commonly used for through-hole components, which have leads (legs) that go through holes in the PCB. This technique allows for fast, reliable, and automated soldering.
🌊 Why Is It Called “Wave” Soldering?
The process gets its name from the wave of molten solder that is created inside the machine. As the PCB passes over this solder wave, the component leads come into contact with it and are instantly soldered in place.
🛠️ How Does It Work?
The wave soldering process usually involves four main steps:
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Fluxing
A layer of flux is applied to the bottom of the PCB. Flux helps remove oxidation and improves the flow of solder. -
Preheating
The board is gently heated to prevent thermal shock and to activate the flux. -
Soldering
The PCB moves over a wave of molten solder. The solder touches the exposed metal parts and forms strong electrical connections. -
Cooling
The soldered board is quickly cooled down to solidify the joints and ensure stability.
🧩 What Is It Used For?
Wave soldering is ideal for:
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Through-hole components
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High-volume production
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Mixed-technology boards (where both surface-mount and through-hole components are used)
It is not suitable for small surface-mount components, which are usually soldered by reflow soldering.
🆚 Wave Soldering vs. Reflow Soldering
| Feature | Wave Soldering | Reflow Soldering |
|---|---|---|
| For components | Through-hole | Surface-mount (SMT) |
| Solder application | Solder wave bath | Solder paste + heating |
| Main usage | THT or mixed boards | SMT assemblies |
🧠 Summary
Wave soldering is a fast and efficient way to solder large numbers of through-hole components. It plays a vital role in electronics manufacturing and continues to be widely used, even in an age of surface-mount technology.