Patent ID: 8545137
Filing Date: 2013-10-01
Classification: B23B,B23C,B23Q,C21D,C22C,Y02P,Y10T

Abstract:
1. A cutting method of a steel for machine structural use, the method comprising: forming a mist by mixing a cutting fluid supplied at a supply rate of 0.01 ml/hour to 200 ml/hour and an oxidizing gas containing, by volume %, 25 to 50% of oxygen, wherein, when a flow rate of the oxidizing gas is defined as Q (1/minute) and the supply rate of the cutting fluid is defined as q (ml/hour), a ratio of q/Q satisfies 0.001 to 1; and cutting the steel for machine structural use while the mist is blown on a cutting edge surface of a tool and a surface of the steel for machine structural use, wherein the steel for machine structural use includes, by mass %: C: 0.01% to 1.2%; Si: 0.005% to 3.0%; Mn: 0.05% to 3.0%; P: 0.001% to 0.2%; S: 0.001% to 0.35%; N: 0.002% to 0.035%; Al: 0.05% to 1.0%; and the balance consisting of Fe and inevitable impurities, and wherein O is limited to 0.003% or less, and the amount of Al [Al %] and the amount of N [N %] satisfy [Al %]−(27/14)×[N %]≧0.05.