Some 30 years ago, an old-timer taught me a simple trick for grinding aluminum. Aluminum is tricky to grind because it always wants to weld itself to the grinding wheel. The typical recommendation is to use a silicon carbide wheel. The first problem with that those wheels are specials more often than not. The other problem is that it doesn't really solve the issue of the stickiness of the aluminum. The old timer taught me to take a standard 46 grit, J grade aluminum oxide wheel and pre-load the wheel using waxy lubricant stick. He used to use Formax F-200 Wheel Wax but I have found that Tapmatic Edge Lube does the job, as well. I would imagine that any hard waxy lubricant stick would be just fine. Just mount the wheel as usual, turn on the grinder, and press the wax stick into the spinning wheel. The lubricant fills the pores of the wheel so that the aluminum has nowhere to go. Keep your grinding fluid directed as close to the point of cut as possible.
Thanks for the tip, Gordon, wherever you are!