METHOD FOR DECISION PRECIPITATION HARDENING EFFICIENCY AT COILING TEMPERATURE OF STEEL ADDED CARBONITRIDES FORMING ELEMENT AND METHOD OF MANUFACTURING STEEL ADDED CARBONITRIDES FORMING ELEMENT USING THE SAME

摘要

PURPOSE: A method of determining the precipitate curing efficiency at the winding temperature of carbo-nitride-forming element bearing steel and a method of manufacturing carbo-nitride-forming element bearing steel are provided to determine the winding temperature of carbo-nitride-forming element bearing steel using the precipitate curing efficiency determined. CONSTITUTION: A method of determining the precipitate curing efficiency at the winding temperature of carbo-nitride-forming element bearing steel comprises next steps. The carbo-nitride-forming element bearing steel wound at a specific winding temperature is austhenized. The austhenized carbo-nitride-forming element bearing steel is quenched. The size of the austhenite grain of the quenched carbo-nitride-forming element bearing steel is measured. The relative precipitate curing efficiency at the winding temperature is determined using the size of the austhenite grain measured.