Silverphos 18

Silverphos 18 is a ternary eutectic, low temperature brazing filler metal that is free flowing and self-fluxing on copper and some high copper and copper alloys by virtue of its phosphorus content. Brasses and most bronzes require the use of a flux for good wetting. This alloy becomes extremely fluid above its melting point. With most joint designs a clearance of 0.001in. to 0.003in. (0.025mm – 0.075mm) is desirable. Silverphos 18 should not be used on ferrous metals or nickel base alloys, since the phosphorus diffuses and produces brittle iron or nickel phosphides at the joint interface.

The properties of a brazed joint are depended upon numerous factors including base metal properties, joint design metallurgical interaction between the base metal and the filler metal. Joints made with Silverphos 18 are entirely satisfactory on copper and soft copper alloys if good fit-up and adequate shear area are maintained. If poor fit-up prevails, or shear area is marginal, a lower phosphorus content silver-copper-phosphorus alloy may be preferred, particularly if the joints are to be subjected to impact or vibration in service.The corrosion resistance of Silverphos 18 is comparable to that of copper except when exposed to Sulphur-containing compounds, especially at elevated temperature. Under these conditions, Silverphos 18 undergoes progressive deterioration. Exposure to pressurized steam can result in accelerated corrosion.