Brazing a 3D stainless product?

Discussion in 'Finishing Techniques' started by dekrakeralex, Feb 22, 2013.

  1. dekrakeralex
    dekrakeralex New Member

    Looking into the process of 3D printing of stainless steel, I read about binders and infusion. Does one end up with a 100% metal (stainless (+bronze)) material that allows for brazing with silver at 600 degC?

    Thanks a lot for your help,
  2. GlenG
    GlenG New Member
    The material silver solders/brazes very well but it takes a little more care than when working on brass or copper. I'm not sure where you are located or what brazing products are available to you? But here is what I know. You should use a high temperature paste flux not jewelers flux. This would be a fluoride based paste, sold by HarrisProducts (and others in the US) You want to use the "black" hi temp version and not the standard "white" flux. I have good results with 45% cadmium free silver alloy. Harris alloy #45-T, flows at 685c. The 56% alloy flows at 652c. Both of these work well and have about the lowest flow temp available. SImiliar products should be available almost worldwide.
    The SS print media has low thermal conductivity and this actually makes soldering/brazing easier in most cases. But It is prone to forming hard black firescale in unprotected areas (like normal steels) so use the flux liberally. Pre-heat slowly, the black flux will visably turn clear when temperature is correct for the solder to flow.
    The whole process is very similar to brazing common steel alloys. So if you fail to make a good joint on the first try you will need to completely clean the whole joint area before a second try. Also note that a clear acrylic is applied to all SW SS parts so clean or bead blast your parts before solder operations begin. This link to Harris Products has a lot of good brazing data. Applications.aspx?cat=Brazing%20and%20Soldering