Solder alloys are made from a mixture of tin, lead, brass and silver. Solder made from tin and lead has a lower melting point, while brass and silver are used to create an alloy able to withstand higher temperatures.
Solder alloy is used to form a permanent connection between electrical components. It is heated using a special tool, called a soldering iron, and the melted solder is then applied to the connecting point of two or more electrical components. Solder alloys are made from electrically conductive metals so as not to impede the function of the components they are used to connect.