Portal:Engineering/Selected picture/35

San Diego (Jan. 4, 2007) Navy Diver 1st Class Josh Moore welds a repair patch on the submerged bow of amphibious transport dock USS Ogden (LPD 5) while the ship was in port at Naval Base San Diego.

Soldering

Credit: Airman Jessica Struble

Soldering 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.