Electron beam polishing of aluminum

A highly polished surface on an aluminum substrate is formed using any number of machining processes. During the machining process, intermetallic compounds are typically generated at a top surface area of the aluminum substrate caused by spot heat generated between the tool edge and the cut tip of the aluminum substrate during the cutting process. The intermetallic compounds can leave surface imperfections after conventional mechanical polishing operations that render the surface of the aluminum substrate difficult to obtain a desired high glossiness due to exfoliation of the intermetallic compounds from the top surface. In order to remove the effect of the intermetallic compounds, an electron beam is applied to the surface resulting in Joule heating to melt down a top surface zone. In this way, any tooling traces and intermetallic compounds are eliminated.