HEAT TREATMENT METHOD FOR SOFTENING HIGH CARBON BEARING STEEL

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method to directly soften a high carbon bearing steel after the hot rolling or the hot forging. ;SOLUTION: In an inline softening heat treatment method, a hot rolled wire and a hot forged parts are primarily cooled to 500-250°C while the cooling speed at 800-500°C is adjusted to 0.5-5°C/second, and then, re-heated to 780-880°C in a short time, and kept at the temperature for the time not exceeding the time expressed by the formula t=530-0.6×T (where, t is the keeping time (second), and T is the re-heating temperature (°C)), and secondarily cooled to 600°C at the cooling speed of 0.1 to 3°C/second.;COPYRIGHT: (C)2001,JPO