| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a high-strength non-heat treated forged part with which a precipitation strengthening corresponding to additional quantity of V can be obtained while suppressing the load of a forging facility and the more strengthening of the forged part can be achieved without increasing the forging cost. <P>SOLUTION: The non-heat treated steel for hot-forging, containing V of 0.20-0.45 mass% is once heated to≥1,100°C, and after applying a primary-forging at the hot-temperature of≥1,050°C, a cooling is performed at the rapid cooling speed of≥10°C/s, and a secondary-forging is successively applied in the temperature range of 580-540°C and thereafter, after successively performing a holding-treatment for holding for≥600 s in the temperature range of 600-540°C, the part is cooled to the room-temperature. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
