ONE-PIECE FORGED TYPE WHEELS OF LIGHT ALLOY HAVING A METAL FLOW METALLOGRAPHIC STRUCTURE

摘要

SUMMARY A one-piece type wheel of light alloy having such a metal flow metallographic structure as having metal flows at least a part of which is continued from the periphery position of the disk part to the outermost diameter position of the outer rim said metal flows moving in a zigzag direction against the contour of the outer rim having a plurality of bending parts and being converged in the outermost diameter periphery part of tile outer rim. This wheel has a high strength and compact metal flows excellent in toughness as well as workability. This wheel having the above described metal flow metallographic strcture is produced by the use of a hot forging apparatus comprising an upper die 6 and a lower die 4, said upper die being provided with an electric heater 7 and with a flash 12 and a gutter 13. 1 5