| 摘要 |
PURPOSE:To produce the the turbine disk, etc., with high productivity at a low cost by pouring the melt of a super heat resisting alloy into a casting mold in a vacuum or inert gaseous atmosphere, applying an external force to the casting mold and oscillation to the mold to prepare a casting preform, then rotary forging the preform. CONSTITUTION:The melt 11 of the super heat resisting alloy is melted in the vacuum or inert gaseous atmosphere. This molten metal 11 is poured into the casting mold (metallic mold) 8 in the vacuum or inert gaseous atmosphere. An eccentric centrifugal force is applied as the external force to the casting mold 8 by using a leg shaft 4, a metallic mold imposing table 5, etc., to oscillate the mold. The casting preform having fine crystal grains are formed by applying the external force. This preform is rotary forged. The crystal grain size of the preform is made to <=100mum. The reduction straining rate at the time of the casting is regulated to <=10 deg.C/sec and >=10<-2>/sec. The finer crystal grains arising from the dynamic recrystal are formed during the casting and the ductility is improved. |
