Soldering

Soldering (AmE: /ˈsɒdərɪŋ/, BrE: /ˈsɒldərɪŋ/), is a process in which two or more items (usually metal) are joined together by melting and putting a filler metal (solder) into the joint, the filler metal having a lower melting point than the adjoining metal. Soldering differs from welding in that soldering does not involve melting the work pieces. In brazing, the filler metal melts at a higher temperature, but the work piece metal does not melt. In the past, nearly all solders contained lead, but environmental and health concerns have increasingly dictated use of lead-free alloys for electronics and plumbing purposes.

There is evidence that soldering was employed as early as 5000 years ago in Mesopotamia. Soldering and brazing are thought to have originated very early in the history of metal-working, probably before 4000 BC. Sumerian swords from ~3000 BC were assembled using hard soldering.

Soldering was historically used to make jewelry items, cooking ware and tools, as well as other uses such as in assembling stained glass.

Soldering is used in plumbing, electronics, and metalwork from flashing to jewelry.

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