Applications of Soft Solders

Alloys can be produced in various forms, including solid wire, flux-cored wire (with flux content ranging from 0.5% to 3.5%), bars, or pre-forms. ST400 and ST300 are recommended for use in environments where ‘soft’ water may corrode conventional tin-lead solders. Alloys containing silver resist silver migration when soldering silver-plated components.

Additionally, special alloys can be created upon customer request.

Thessco Grade Nominal Composition Melting Range (°C) EN 29453 Specifications Comments
Ag Sn Cu Zn Other Solidus Liquidus
ST400 4 96 221 224 28 Good colour match for INOX
ST350 4.5 96.5 221 221 28 Good for narrow joint gaps
ST300 3 97 221 225 29
SC300 97 3 230 250 24 Higher temperature resistance
SC1000 90 10 221 295

Other materials are available upon request – please consult your Sales Office. Safety Data Sheets are available on request