Solder and Soldering Iron

The vast majority of solders are alloys that contain tin, lead, and, sometimes, one or more other metals. For example, the well-known general solder known as plumbers' solder consists of 50% lead and 50% tin. A solder used to join surfaces that contain silver is made of 62% tin, 36% lead, and 2% silver. And a solder that melts at unusually low temperatures can be made from 13% tin, 27% lead, 10% cadmium, and 50% bismuth. The most widely used solders for making electrical connections consist of 60-63% tin and 37-40% lead.

Solder alloys are available in many forms, such as wire, bar, foil, rings, spheres, and paste. The specific kind of solder selected depends on the kind of junction to be formed. Foil solder, for example, may be called when the junction to be formed has a particular shape that can be stamped or cut out prior to the actual soldering process.