Silverphos 18


Silverphos 18 is a moderate cost brazing filler metal suitable for joining copper, brass and bronze alloys where low brazing temperature and free flowing characteristics are requires. It should be used on assembles where good fit-up can be maintained.

Available Forms

Wire, strip, limited engineered preforms, limited specialty preforms per customer specification, powder and paste.


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.


American Welding Society (AWS)



1190 F / 643 C


1230 F / 666 C


The information and recommendations contained in this publication have been provided without charge & compiled from sources believed to be reliable and to represent the best information available on the subject at the time of issue. No warranty, guarantee, or representation is made by the Prince and Izant Company, Inc. as to the absolute correctness or sufficiency of any representation contained in this and other publications; Prince and Izant Company, Inc. assumes no responsibility in connection therewith; nor can it be assumed that all acceptable safety measures are contained in this (and other publications, or that other or additional measures may not be required under particular or exceptional conditions or circumstances.

Silverphos 18 AWS: BCuP-8

Download TDS

Resources Center

We work closely with our customers to provide guidance and support on brazing and medical precious metal related issues.