Process zone P3 is the solder reflow zone. In zone P3, the<br>temperature is quickly raised above the liquidus point<br>of solder to 260°C (500°F) for optimum results. The<br>dwell time above the liquidus point of solder should be<br>between 60 and 120 seconds. This is to assure proper<br>coalescing of the solder paste into liquid solder and the<br>formation of good solder connections. Beyond the recommended dwell time the intermetallic growth within<br>the solder connections becomes excessive, resulting in<br>the formation of weak and unreliable connections. The<br>temperature is then rapidly reduced to a point below<br>the solidus temperature of the solder to allow the solder<br>within the connections to freeze solid.
Sedang diterjemahkan, harap tunggu..
