METHOD FOR PRODUCING HIGH FATIGUE STRENGTH BOLT, AND HIGH FATIGUE STRENGTH BOLT PRODUCED BY THE METHOD

摘要

PROBLEM TO BE SOLVED: To provide a method for producing a high fatigue strength bolt in which the improvement of strength and the improvement of fatigue properties are made consistent by simple means, and a high fatigue strength bolt produced by the method.SOLUTION: Provided is a method for producing a high fatigue strength bolt obtained by subjecting a bolt made of steel molded into a prescribed shape to quenching and tempering and further subjecting the same to aging treatment, being holding for 10 min to 735 days at 20 to 300°C, in which λ obtained by formula (1) from an aging temperature T(°C) for an aging time t(hr) satisfies 7100<λ<12000, and a high fatigue strength bolt produced by the heat treatment and aging treatment: λ=(T+273)×(logt+20) (1).