均匀化退火和锻造对双相耐磨钢强韧性的影响

研究了一种低合金双相耐磨钢经均匀化退火和锻造处理后的微观组织和强韧性能.结果表明:经980℃均匀化退火4,8 h和1 150℃锻造处理后,实验钢显微组织主要为板条状马氏体、针状贝氏体及少量残余奥氏体,锻造处理后的晶粒度最小为7.0~7.5级,均匀化退火处理后的晶粒度最大为6.5~7.0级.均匀化退火的保温时间是影响双相耐磨钢力学性能的主要因素,实验钢保温4 h时的冲击韧性和延伸率值高于保温8 h的值.锻造比均匀化退火更适宜于提高低合金双相耐磨钢的强韧性,优化工艺为始锻温度1 150℃、终锻温度800℃、锻造比2.

Effects of Homogenizing Annealing and Forging on Strength and Toughness of Dual-Phase Wear Resistant Steels

The effects of homogenizing annealing and forging on the microstructure， strength and toughness of the dual-phase wear-resistant steel were investigated. The results showed that the microstructure of the steel contained mainly lath martensite， acicular bainite and a little retained austenite under 980℃ homogenizing annealing for 4 and 8hrs respectively and 1150℃ forging. The minimum grain size of the steel is No.7.0~7.5 grade after forging while the maximum grain size of the steel homogenized is No.6.5~7.0 grade. The holding time of the homogenizing annealing is the main factor that affects the mechanical properties of dual-phase wear resistant steels， and the impact toughness and elongation values of the test steels holding for 4hrs are higher than that of the test steels holding for 8hrs. Forging deformation improves the strength and toughness of dual-phase wear resistant steels more significantly than that under homogenizing annealing， and the optimized process parameters were as follow with initial forging temperature of 1150℃， final forging temperature of 800℃ and forging ratio of 2.