... , plumbing, and assembly of sheet metal parts. Manual soldering uses a soldering iron or soldering gun. Alloys that melt between ... 840 °F) is called 'hard soldering', 'silver soldering', or brazing.Lead-free solders in commercial use may contain tin, copper, silver ... bismuth, indium, zinc, antimony, and traces of other metals. Most lead-free replacements for conventional Sn60/Pb40 and Sn63/Pb37 solder ...