Tom442

This is a silly question...but I bead blasted the paint off the wiper arms last night. The material shown in the picture at the mount end of the arms seems to be aluminum? (magnet doesn't stick to it at all, the rest of the arms seem to be stainless) Does anyone know for sure? The fresh blasted finish looks good...but if it is some kind of pot metal..it will rust? Sure I could give it a quick shot of paint.
Thanks
Tom
68 442 convt getting put back together
70 F85 Sports Coupe
98 Aurora
Radio Flyer