does anyone know if stainless steel needs to be isolated from CF like aluminum? Google throws up conflicting answers.
No neither does titanium. A good pickle helps bonding.
In the end, they are dissimilar conductive materials. They WILL if they can. Maybe slower than other metals, but they will corrode. Play it safe and use a light scrim of glass or kevlar. You can try anodizing as well, it might cause the TiO2 skinning to be the insulator.
Check the galvanic chart. All stainless alloys are better than aluminum but some are still pretty poor. The best are the austinitic grades like 316, 317 which are all pretty close to titanium.
It really just depends on your application if it will be a problem or not. Carbon + SS + saltwater is not a happy mix. Much better than aluminum, but it will still corrode at an accelerated pace
True. I have galvanized bolts AND brass bolts in some carbon parts on my bike for a few years now, with no ill-effects. However, also not structural parts.
Thanks for the feedback. I can’t say too much about what this is for but I need to connect 3D printed SS parts to CF. Scrim and pickle are not an option for optical reasons. I guess I’ll need to test with salt water and heat.
Can you be more specific that a scrim would not work for optical reasons? It will be sandwiched between the CF and the metal, and is generally only a few microns thick.
the metal has a lattice shape where the carbon shows through between struts. I would have to cut it out there which would take forever. It’s going to be a PITA to clean the glue out that smears there as it is.
We isolate and insulate as routine practice.
In a marine environment stainless corrodes rapidly.
We have several products that are employed to keep the effects to a minimum… Tef Gel is one for removable fastners and moving items, Duralac is another that works well on all metals, even preventing corrosion when using anodised alloys in contact with carbon.
I have noticed that Ti does corrode to some degree, but its more a discolouration/tarnishing than anything else.
A layer of 120 gsm or lighter fiberglass should give you the insulation you need while still letting the carbon show through, no need to trim it where the metal isn’t
I’m using DP490, which turns the glass black. I don’t know of any suitable bonding epoxy that is clear. If you do I would love to hear.