I do soda blasting as a little side income, the issue with paint sticking is true if not prepped properly, we use and suggest 10 percent vinegar in water, it will foam a little and if it is steel be ready to dry it and paint fast or it will rust. I have a fender hanging in my barn half sand blasted half soda, it is 2 years old the sand side rusted in less than a week the soda side has not rusted yet. as far as the aluminum goes if it was polished it will be smooth but hazy if it is a casting it will more than likely look better than new. I dont recommend trying to blast soda in a sand blaster,you wont get the desired result because you cant meter the soda very well. as far as sand blasting, the base material dose not heat up it gets thinned out and pushed around,just the same as you had a hammer and a small prick punch. I have personally myself purposely blasted a hole through a jap fender and put my hand on it it was cold. any more questions feel free to ask I have dealt with all kinds of materials