Reflow soldering works differently than wave soldering:
Step 1: Apply solder paste
A special sticky paste (containing both solder and flux) is spread onto the circuit board using a stencil (like a template).
Step 2: Place parts
A machine picks up electronic parts and puts them on the paste. The paste acts like glue, holding parts in place.
Step 3: Heat in the oven
The board moves through a soldering oven on a conveyor belt. Inside:
- Preheat Zone: Gently warms the board to prepare it.
- Thermal Soak Zone: Activates the flux (cleaning agent) in the paste.
- Reflow Zone: Temperature rises above the solder’s melting point, turning the paste into liquid to bond parts.
Step 4: Cool
Finally, the board cools, hardening the solder to lock parts securely.
Simplified Advantages of Reflow Soldering:
- Top-quality results: Creates reliable connections trusted by both manufacturers and customers.
- Perfect for surface-mount (SMT): Best method for modern circuit boards with tiny parts soldered directly to the surface.
- Great for mass production: Fast and efficient for making many boards at once.
- Works with any SMT part: Handles all kinds of tiny electronic packages (like chips, resistors, etc.).
- Easy process control: Temperature and timing are simple to monitor and adjust.
- Precise solder amounts: Uses just the right amount of solder, preventing defects like bridging (where solder accidentally connects two parts).
- Gentler on parts: Minimizes heat damage to sensitive electronics during soldering.
