A-Soldering-Processes-Custom Design Circuit
Board Electronic Pcb
There are three forms of soldering, each requiring progressively higher temperatures and producing an increasingly stronger joint strength:
soft soldering, which originally used a tin-lead alloy as the filler metal
silver soldering, which uses an alloy containing silver
brazing which uses a brass alloy for the filler
The alloy of the filler metal for each type of soldering can be adjusted to modify the melting temperature of the filler. Soldering differs from gluing significantly in that the filler metals alloy with the workpiece at the junction to form a gas- and liquid-tight bond.
Soft soldering is characterized by having a melting point of the filler metal below approximately 400 °C (752 °F), whereas silver soldering and brazing use higher temperatures, typically requiring a flame or carbon arc torch to achieve the melting of the filler. Soft solder filler metals are typically alloys (often containing lead) that have liquidus temperatures below 350 °C.
In this soldering process, heat is applied to the parts to be joined, causing the solder to melt and to bond to the workpieces in an alloying process called wetting. In stranded wire, the solder is drawn up into the wire by capillary action in a process called 'wicking'. Capillary action also takes place when the workpieces are very close together or touching. The joint's tensile strength is dependent on the filler metal used. Soldering produces electrically-conductive, water- and gas-tight joints.