| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a wire or a bar having excellent cold forging property in which carbide can be sufficiently, uniformly and easily spheroidized in a hot rolling line. SOLUTION: After performing the finish rolling out of the hot rolling so that the finish rolling reduction rate of area is≥15% in the temperature range of≥Ar<SB>1</SB>-200°C and≤Ar<SB>1</SB>+100°C, steel after the finish rolling is once cooled to the temperature range of≤Ar<SB>1</SB>, re-heated to the temperature range of≥Ac<SB>1</SB>and≤Ac<SB>3</SB>or Acm, and, then, cooled to the cooling stop temperature of≤600°C at a cooling rate of≤0.05°C/s. COPYRIGHT: (C)2005,JPO&NCIPI
|
