| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a forged component in which a portion to which sufficient yield strength and ductility are imparted (portion to be highly strengthened) and a portion whose yield strength is suppressed (portion to low strengthened) for improving a cutting property in a non-heat treated manner within one component. SOLUTION: The method includes: a heating treatment process of heating a workpiece to reach T<SB POS="POST">N</SB>bc (°C); a hot forging process of controlling the temperature of the workpiece to≥1,050°C and performing hot-forging and controlling the true strain amount of the workpiece to≥0.3 by the hot forging; and a cooling process of cooling the workpiece in such a manner that, regarding the portion to be highly strengthened of the workpiece, an average cooling rate up to a rapid cooling stop temperature is controlled to≥3.0°C/s and an average cooling rate from the rapid cooling stop temperature to 400°C is controlled to 0.1 to 1.5°C/s, and regarding the portion to be low strengthened of the workpiece, the average cooling rate up to 600°C is controlled to≤1.0°C/s. COPYRIGHT: (C)2012,JPO&INPIT |
