345MPa级别耐火钢模拟火灾状态下的组织演变  

Microstructure evolution of 345 MPa grade fire-resistant steel under fire simulation

作　　者：刘明[1] 侯华兴[1] 林田子[1] 王小强[2] 隋轶[3] 

机构地区：[1]鞍钢股份有限公司技术中心,辽宁鞍山114009 [2]鞍钢股份有限公司中厚板厂,辽宁鞍山114021 [3]鞍钢股份有限公司产品制造部,辽宁鞍山114009

出　　处：《金属热处理》2013年第10期22-26,共5页Heat Treatment of Metals

基　　金：国家自然科学基金(50661003)

摘　　要：利用光学显微镜、透射电镜等分别对模拟火灾状态下耐火钢的显微组织、M-A岛的变化进行分析,研究了高温下钢中析出相情况。结果表明,试验耐火钢的组织是由铁素体、少量粒状贝氏体和M-A岛组成的混合组织;在高温状态下,试验耐火钢的强度和显微硬度有所下降,但大部分M-A岛都表现出较好的稳定性;Nb和Ti的碳氮化物在基体或晶界析出所形成的第二相质点,以析出强化的方式来提高钢的高温强度。The evolution of microstructure and M-A islands of fire-resistant （ F-R） steels under fire simulation were analyzed by means of OM and TEM.The precipitated phases in F-R steel were studied .The results show that the microstructure of the tested F-R steels is the mixture of ferrite matrix, little granular bainite and M-A islands.At higher temperature, strength and microhardness of F-R steel decrease, most of M-A islands keep stable , Nb and Ti carbonitride form the second phase particles in the matrix or grain boundary , and it improves the strength of the steels at high temperature by precipitation strengthening .

关 键 词：耐火钢 模拟火灾 微观组织 M—A岛 析出相 

分 类 号：TG142.73[一般工业技术—材料科学与工程]