冷轧耐候双相钢连续冷却转变及过时效工艺研究  

Study on continuous cooling transformation and its over-aging process of cold rolled atmospheric corrosion resisting steel

作　　者：孙国胜[1] 王小鹏[1] 杜林秀[1] 

机构地区：[1]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110819

出　　处：《轧钢》2014年第5期1-5,共5页Steel Rolling

基　　金：国家科技支撑计划项目(2011BAE25B03)

摘　　要：为了探索一种冷轧超高强耐候双相钢的连续冷却转变规律以及过时效温度对其组织性能的影响,利用Formaster-FⅡ全自动相变仪和连续退火模拟试验机进行了CCT曲线的测定和连续退火实验。结果表明:实验钢的过冷奥氏体在冷速为0.5℃/s时已有马氏体转变的发生,组织为先共析铁素体+贝氏体+马氏体;当冷速为80.0℃/s时,仅发生马氏体转变,组织为残留铁素体+马氏体。低温过时效时,马氏体呈板条状结构;过时效温度为350℃时,板条马氏体已经出现分解。随着过时效温度的升高,实验钢的屈服强度和抗拉强度呈下降趋势,伸长率则随过时效温度的升高而增加。This research mainly focused on the continuous cooling transformation of a kind of high strength cold rolled at-mospheric corrosion resisting steel and effects of over-aging temperature on its microstructure and properties, tsontmuous cooling transformation curve was measured by Formaster-FⅡ automatic expansion instrument, and annealing experiments were performed by continuous annealing simulator. The results show that martensite transformation occurred at the cooling rate of 0.5 ℃/s, the microstructure is composed of proeutectoid ferrite ＋ bainite ＋ martensite, only martensite transforma- tion occurred at the cooling rate of 80.0 ℃/s, the microstructure is composed of residual ferrite ＋ martensite. When over-ag- ing temperature is low, martensite presented lath-shaped, martensite decomposed obviously when the over-aging tempera- ture is 350 ℃. With the over-aging temperature increasing, the tensile strength and yield strength are decreased, and the elongation is increased.

关 键 词：冷轧耐候钢 连续冷却转变 过时效 组织性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]