Can I use Glass Bubbles in resin to prevent galvanic corrosion between carbon fibre and aluminium?
To prevent galvanic corrosion, any physical barrier will work, such as a layer of resin, layer of woven fibreglass etc. so yes, glass bubbles mixed in with resin would work (as would resin on its own). It would not work to just mix bubbles into the resin and then use the resin to laminate (wet-out) carbon fibre because you're not creating a proper barrier.