Solder and Soldering Iron

Soldering is the process by which two pieces of metal are joined to each other by means of an alloy. The tool used to make this kind of joint is called a soldering iron, and the alloy from which the connection is made is called a solder. Soldering can be used for making either a mechanical or an electrical connection. An example of the former case is the situation in which a plumber uses plumbers solder to connect two pieces of pipe with each other. An example of the latter case is the situation in which a worker connects an electrical wire to a printed board.

The technique of soldering has been known to human artisans for many centuries. Some metal work recovered from the remains of ancient Egypt and Mesopotamia, for example, contains evidence of primitive forms of soldering. As workers became more familiar with the properties of metals in the late Middle Ages, soldering became a routine technique in metal work of various kinds.