热处理对DH36钢的微观组织演化与性能的影响  

Effect of Heat Treatment on Microstructure and Plastic Flow Characteristics of DH36 Steel

作　　者：孔德拴[1] 郭伟国[1] 孟卫华[1] 王亚妮[1] 

机构地区：[1]西北工业大学航空学院,陕西西安710072

出　　处：《热加工工艺》2013年第6期185-190,共6页Hot Working Technology

摘　　要：为了揭示热处理工艺对冷轧合金钢DH36微观组织及其塑性流动特性的影响,在实验室对DH36冷轧钢进行5种不同工艺过程的热处理,结合力学试验、扫描电镜和X射线能谱分析,对不同热处理工艺下的微观组织演化和塑性流动特性进行了深入分析。结果表明:DH36钢经α和γ两相区不同温度退火后,微观组织中的珠光体减少,铁素体增多,但流动应力变化的幅值相同;对比发现,经880℃淬火和700℃回火的DH36钢具有比冷轧态DH36钢更高的塑性流动应力,这主要归功于弥散分布的颗粒状碳化物的沉淀强化作用,以及晶粒中存在大量的亚晶界;DH36钢中的DSA现象出现在一个较宽的温度范围内,DSA应力峰值处的激活能为234kJ/mol,这可归于置换溶质原子与运动位错的相互作用。To understand the effect of heat-treatment on the microstructure and plastic flow characteristics of DH36 steel, five heat treatment technologies were carried out. The microstructure evolution and the plastic flow characteristics were analyzed by SEM and EDS, combined with systematic mechanical test. The results show that： when the DH36 steel is annealed in α and γ phases area with different temperatures, the pearlite reduces but the ferrite increases, flow stress deline is the same; when quenching at 880℃ and tempering at 700℃, DH36 steel will possess a higher flow stress, this is mainly attributed to the disperse distribution of the granular carbide precipitation; The DSA in DH36 steel appears in a wide temperature range, the activation energy for the maximum flow stress is 234 kJ/mol, the mechanism is the interaction of diffusion substitutional atoms and moving dislocation.

关 键 词：DH36 塑性 热处理 DSA 微观组织 

分 类 号：O344.4[理学—固体力学]