We did the metal flame test demo last year using the PLOTS spectrometer. I thought we had tested aluminum, but it doesn't look like we photographed it for the write-up. My memory is that it glows red and starts to melt.
Flame tests are typically looking for emission spectrum, which you would look for with a spectrometer and which are temperature independent. Aluminum has very faint spectral lines, so you probably wouldn't be able to see it with a spectrometer (we looked but didn't see anything). You will be able to see blackbody ("red" hot, "white" hot, "blue" hot) depending on temperature. For instance, a magnesium strip burns bright white but steel wool burns red -- that's because magnesium burns hotter.