Q: I want to use A286 fasteners with our product (a force sensor). Will A286 gall with 6Al4V titanium or 15-5 stainless steel or 304 SS helicoils without lubrication. The customer will not allow lubricants. Thank you
A: The biggest factor to galling is using similar material on each other. The fact that you are using dissimilar materials that will greatly reduce the chances of galling. Another thing you could do is silver plate the A286 fasteners. The silver plating will act as an anti-galling agent and avoid any kind of lubricant.
You could get more details about galling at the following links: https://www.specialfastenersbolt.com/
I would be cautious about the “similar material” rule-of-thumb. For instance 17-4PH will gall against many other materials, while Nitronic 60 is not prone to galling when self-mated. For the application above, I suggest you use Nitronic 60 Helicoils.