The invention comprises a method and apparatus for equal channel angular extrusion (ECAE) of flat billets to control material structure and properties. The improvements of the method include the special systems of billet orientations, billet lubrication, billet ejection from dies, and a press/die control system those eliminate surface cracks, flashes and billet reshaping or deburring between passes. Therefore, multi-pass ECAE becomes a cost-effective industrial operation and may be applied to large billets.