A vehicle door beam and related methods of making door beams include a flat-rolled aluminum alloy sheet, where two edges of the sheet that are transverse to the roll direction of the sheet are brought together to form a tube. The two edges are friction stir welded together to form a butt joint along a length of the tube. The tube is arranged, along with other optional components, as a side-impact door beam in a vehicle door, such that the butt joint is facing away from an expected impact direction of the vehicle door.