An aluminum welding system includes a welding machine configured to weld a workpiece with an aluminum nugget and a measurement device configured to measure an attribute of at least one of the aluminum nugget and a welding process. The system further includes a processing device configured to output a weld quality signal representing a quality of an aluminum weld based at least in part on the attribute measured. A method includes measuring an attribute of at least one of an aluminum nugget forming a joint of a workpiece and a welding process, determining a quality of an aluminum weld based at least in part on the attribute measured, and outputting a weld quality signal representing the determined quality.