氮含量和TMCP对微合金V-N钢显微组织和力学性能的影响  

Effects of nitrogen content and TMCP on microstructure and mechanical properties of V-N micro-alloying steels

作　　者：尹桂全[1] 黄贞益[1] 杨才福[2] 方芳[2] 姜辉[1] 郑建平[1] 程坚平[3] 程晓舫[3] 陈斌[3] 

机构地区：[1]安徽工业大学材料科学与工程学院 [2]北京钢铁研究总院结构材料研究所,北京100081 [3]马鞍山钢铁公司技术中心,安徽马鞍山243000

出　　处：《金属热处理》2008年第3期4-8,共5页Heat Treatment of Metals

基　　金：安徽省教育厅自然科学研究重点项目(2006KJ080A)

摘　　要：研究了含氮量和第三代热机械加工工艺(TMCP)参数对低碳微合金V-N钢力学性能和显微组织的影响。对系列超高氮和超低碳含量的微合金V-N钢进行了不同工艺的控制轧制,对轧后试样进行了力学性能测试、显微组织观察以及晶粒大小的测定。结果表明,试验钢中氮含量的增加及终轧温度的降低均可使晶粒细化,强度相应提高,但钢中N含量过高显著损害塑性。试验钢高温变形奥氏体中析出微细VN粒子,该粒子诱导轧后冷却期间γ→α相变初期晶内铁素体的生成,产生细晶强化,是V-N微合金钢的重要强化机制之一。The effects of nitrogen content and third generation thermo-mechanical control process（TMCP） parameters on microstructure and mechanical properties of V-N microalloyed low carbon steels were studied. The series V-N steels containing the super-high nitrogen and ultra-low carbon were rolled by different process. The mechanical properties of the specimens after rolling were tested. Microstructures were observed and grain size was measured. The results show that increasing the nitrogen content and decreasing the final rolling temperature of the steels all can refine the grain size effectively and increase the strength correspondingly. Too high a nitrogen content can damage the ductility remarkably. The fine VN particles precipitated from austenite at high temperature were observed in typical rolling specimens using TEM. The fine second phase particles VN induced intragranular ferrite nucleation at initial period of γ→α transformation after rolling. Refine grains function of second phase particles is one of the important strengthening mechanism in the microalloyed V-N steels.

关 键 词：超低碳微合金V-N钢 第三代热机械加工工艺 力学性能 显微组织 VN粒子 

分 类 号：TG142.33[一般工业技术—材料科学与工程]