热变形对钒氮微合金钢连续冷却相变的影响  

Effect of Thermal Deformation on Continuous Cooling Transformation Behaviors of V-N Microalloyed Steel

作　　者：赵宝纯[1] 赵坦[1] 李桂艳[1] 鲁强[2] 

机构地区：[1]鞍钢股份有限公司技术中心,辽宁鞍山114009 [2]鞍钢股份有限公司鲅鱼圈钢铁分公司,辽宁营口115007

出　　处：《钢铁钒钛》2014年第2期113-117,共5页Iron Steel Vanadium Titanium

摘　　要：在Gleeble-3800热力模拟试验机上,进行了钒氮微合金钢在未变形和多道次轧制条件下的模拟试验,通过热膨胀法和金相-硬度法,建立了试验钢的静态和动态CCT图;应用光学显微镜、扫描电镜(SEM)和透射电镜(TEM)对组织和析出相进行了观察,分析了变形条件对显微组织的影响,研究了该试验钢的连续冷却相变行为。结果表明,变形促进了铁素体和珠光体相变,在较大冷速下获得了一定量的铁素体组织。同时变形也促进了钒的碳氮化物析出,利于铁素体相变以及组织的细化。在两种条件下,均可获得一定量的贝氏体组织,且在较大冷速下的贝氏体转变开始温度有所升高。Simulation tests were performed on a Gleeble-3800 thermo-mechanical simulator to study the transformation behaviors of V-N microalloyed steel without deformation or under multipass deformation conditions. The corresponding static and dynamic CCT diagrams of the tested steel were made by analyzing the dilatometric curves and microstructures combined with hardness measurement. Based on the observation of microstructures and precipitates by optical microscopy, SEM and TEM, the effects of deformation on microstructures were analyzed and the continuous cooling transformation behaviors of the tested steel were studied. The results show that the transformation of both ferrite and pearlite is promoted by application of strain and ferrite transformation occurs at a higher cooling velocity. At the same time, deformation promotes the precipitation process of vanadium carbonitride, which leads to ferrite transformation and microstructure refinement. Bainite is obtained at a wide range of cooling velocity regardless of the strain and the starting temperature of bainite transformation goes up at a higher cooling velocity.

关 键 词：钒氮微合金钢 热变形 CCT图 析出相 

分 类 号：TG142.33[一般工业技术—材料科学与工程]