Material that doesn't like galvanizing (Zn)

[GSSTUART]

I hope that this forum is meant to be used to ask questions about material properties. I am looking for a material that will be operating in the temperature range of 300-800 deg. F. that will have an expanded metal (.012" thick) rubbing against it with 20-50 lbf . This expanded metal is galvanized and I am having trouble with the galvanizing (Zinc) softening and transferring to the 304 Stainless Steel heater bars (material to be replaced/improved) that it rubs against. The expanded metal moves relatively slowly 2-6 ft./min. and must be in contact with the heater bars for this process. I originally tried 1018 cold rolled steel and that was much worse. The galvanizing operation next to our plant told me that SS was the worst material for them to galvanize (why someone would want to galvanize SS I don't know) so I went to that material and got some improvement. The fact that the 2 metals are in constant sliding contact requires low friction and long wearing attributes for best service. Any help appreciated.

Thanks
Gary

[Geof]

From your description it sounds like the stainless steel heater bars are heating the expanded metal??? So they have to be in contact, but bthe expanded metal moves, sliding against the stainless steel.

I think you will have problems sliding any type of steel against the hot stainless bars. A thing you could try is clamping thin bronze strips against the stainless so that the bronze is the material in contact with the expanded metal. You should find it will slide better, and it has a fairly good thermal conductivity so it should transfer the heat okay.