研究論文
2¼Cr-1Mo鋳鋼の機械的性質に及ぼす熱処理条件の影響
1977 年 49 巻 8 号 p. 489-494
詳細
1977 年 49 巻 8 号 p. 489-494
The effect of quality heat treatment condition on the mechanical properties and temper embrittlement of 2¼Cr-1Mo cast steel for turbine cylinder castings are presented in this paper. Mechanical properties after quality heat treatment were shown as a function of the cooling rate from austenitizing temperature and Larson-Miller's tempering parameter.
When the cooling rate was faster than 20°C/min, uniform bainite or mixture of bainite and martensite with no blockish ferrite, which caused excellent mechanical properties, was obtained and tensile and impact properties were improved with the increase of tempering parameter. The degree of temper embrittlement 2¼Cr-1Mo cast steel is affected by chemical composition and heat treatment. It has been proved that the lower temper embrittlement parameter and the cooling rate faster than 30°C/hr from tempering temperature are necessary to obtain excellent notch toughness.
