| 摘要 |
PURPOSE:To obtain a highly precise turntable having close composition and even internal structure without requiring secondary mechanical work, by making a hot forging material of aluminum alloy plastic by a 450-550 deg.C heat treatment and performing press-forging. CONSTITUTION:As a hot forging material of aluminum alloy, a billet bar having a diameter about a half that of a turntable and prescribed weight is used and heated at about 450-550 deg.C in a hot blast circulation furnace to obtain plasticity. Then, the billet is applied with 1-5t/cm<2> by a press forging machine to be formed into an extremely strong turntable by elongating a forging flow line radially and uniformly, and it is cooled naturally or heat-treated by quenching, etc. Thus, the highly precise turntable having close composition and uniform internal structure is obtained without secondary mechanical work. |
