METHOD FOR STRUCTURE FORMATION OF METALS AT INTENSIVE PLASTIC DEFORMATION AND APPARATUS FOR PERFORMING THE SAME Russian patent published in 2002 - IPC

FIELD: plastic metal working, namely preparation of blank material for further working by die forging processes. SUBSTANCE: method comprises steps of closed upsetting; then successive backward-through and forward-through extrusion of one end of blank; repeating process at other end of blank. Above mentioned operations of die forging are realized in apparatus having two dies and two punches. One punch is round; it has round inner edge at one end. Second punch is arranged inside first one. Die in which blank is placed is mounted on plate with rough surface. Such design of apparatus and method allow to receive nanocrystalline structure of metal during less number of working cycles due to increased deformation degree for cycle. EFFECT: increased size of blanks, shortened working cycle. 2 cl, 4 dwg