Soldering terminology

When an alloy of two metals (A and B) is heated, such as a eutectic alloy, A and B will start to melt even before reaching their respective melting temperature. Similarly, when molten solder comes into contact with another metal, the metal melts and forms an alloy with the solder even if it has a higher melting point than the solder. For example, the melting temperature of copper is 1,083 ° C, but it melts at 250 °C when it gets into contact with molten solder. A silver coating on a PCB also dissolves in the solder and forms an alloy with it. This process is known as leaching. However, the term is also used in metallurgy for the process of withdrawing a certain substance from a solution with several components.