TITANIUM ALLOY PIPE EXPANDING DIE Russian patent published in 1998 - IPC

FIELD: plastic working of metals in aircraft, ship-building and related industries. SUBSTANCE: die has dielectric supporting plate, conical punch and pusher. Conical punch is assembled from dielectric and current-conductive metal members secured on common shaft. Current-conductive ring provides supplying of pulsed electric current to billet. Minimum diameter D(min) of current-conductive ring is calculated by equation recited in Specifications. Such construction allows deformation extent of difficult-to-deform titanium alloys to be increased by 10% as compared to known construction requiring heating. EFFECT: increased efficiency, reduced labor intensity by eliminating formation of gas-saturated layer on billet surface and, as a result, elimination of additional finishing layer removal operations. 1 dwg