Method of treating steel with reduced pressure carburizing and nitriding

摘要

To provide a reduced pressure carburizing / nitriding treatment method with optimum conditions in a case where the decompression carburizing treatment and the nitriding treatment are carried out continuously and a mass production furnace is used as a heat treatment furnace performing at least nitriding treatment To do.SOLUTION: A mass production furnace is used as a heat treatment furnace in which a reduced pressure carburizing treatment and a nitriding treatment are continuously performed on a steel material containing Cr of 0.18 to 2.00% by mass and at least nitriding treatment is performed . The nitriding treatment is carried out at a treatment temperature T ( C.) in the range of 900 C. to 970 C., and the atmospheric pressure P (Pa) is the upper limit PH (Pa) which is a low value of PH 1 and PH 2 and the upper limit PH PL 2 in the range of the lower limit PL (Pa) which is the lower value of the lower limit PL 2. PL1 = 72000, PL2 = (-65.1 T + 51000) [Cr] + T 464-356150BACKGROUND OF THE INVENTION