Abstract: A process and a device for manufacturing an extruded section of an aluminum alloy containing additions of boron or compounds thereof are intended to simplify the manufacture of aluminum alloy sections for use in nuclear science and technology. Using a boron-containing aluminum-based raw material a section is to be formed such that its design ensures adequate stability and at the same time the necessary screening properties. To this end a billet having a core of aluminum alloy with additions of boron or the like and a mantel surrounding the same is manufactured and hot formed by extrusion, such that, using the molten metal route or powder metallurgy, a blank of aluminum alloy of particular alloy groups with additions of boron or its compounds at a concentration of 0.05 to 50 wt % is taken as the starting basis.