Shear assisted processing and extrusion (ShAPE (Trademark) ) will be used to join dissimilar materials such as magnesium and aluminum alloys in a butt joint configuration. Combinations of 2XXX, 6XXX, and 7XXX aluminum or other alloys or other materials could also be joined in extruded form. Because joining will occur in the solid-phase and in the presence of extreme shear ,the joint composition will transition gradually from one material to another which will improve mechanical properties compared to conventional fusion welding. This a solution for joining extruded materials such as Mg-Al and precipitation hardened high strength aluminum alloys which are not readily joined by fusion welding. This new joining concept builds upon recent discoveries, and years of experience, gained using ShAPE (Trademark) to extrude magnesium and aluminum alloys. This concept is an entirely new joining method.