摘要
研究了回火温度对高硅中碳和中低碳MnB系贝氏体钢强韧性的影响。结果表明,硅含量增加可提高贝氏体钢的回火抗力,中碳和中低碳钢的屈强比在400℃回火后分别达到087和089。300℃回火使两种实验钢的韧度达到最大值,分别为76J/cm2和96J/cm2。450～500℃回火出现韧度的最低值,即出现贝氏体冲击回火脆性。分析认为贝氏体回火脆性与残余奥氏体的分解有关。
Effect of tempering temperature on the strength and toughness in medium and medium\|low carbon Mn\|B bainitic steels containing higher silicon contents was mainly studied in this paper. The results show that increase of silicon contents in Mn\|B bainitic steel can raise the tempering resistance of steels and the rate of σ \-s/ σ \-b of medium and medium\|low carbon steels is 0.87 and 0.89 after tempering at 400℃ respectively. The best impact toughness is obtained tempered at 300℃, its value is 96J/cm\+2 and 76J/cm\+2 respectively. The lowest impact toughnes is got when tempered at 450～500℃,called as tempered bainite brittleness. We consider that the temper bainite brittleness is related to the decomposition of retained austenite in steels.
关键词
贝氏体钢
回火脆性
强韧性
回火温度
bainitic steel, temper brittleness, strength and toughness
