控轧控冷工艺条件下X70针状铁素体管线钢铌、钛的析出行为  

Precipitation of Acicular Ferrite Pipeline Steel X70 in Thermomechanically Controlled Processing

作　　者：孙毅[1] 张立红[1] 于浩[1] 康永林[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083

出　　处：《机械工程材料》2006年第8期10-12,44,共4页Materials For Mechanical Engineering

摘　　要：通过透射电镜研究了X70针状铁素体管线钢中微合金元素铌、钛在控轧和控冷过程中的析出行为。结果表明:析出粒子主要以两种形式存在,一种是在高温下尺寸较大的铌、钛复合粒子的析出,方形的TiN粒子先析出,随后含铌的粒子将包覆在TiN外面并以其为核析出,而不是独立形核;另一种是在低温条件下,由于变形使大量细小的近似球形的NbC在晶内的位错和亚晶上析出。同时还讨论了控轧控冷技术对第二相粒子析出的促进作用。The precipitation behaviors of micro alloy Nb, Ti elements in acicular ferrite pipeline steel X70 in thermomechanically controlled processing were investigated by using transmission electron microscopy. The precipitates observed by TEM were in two forms. The large precipitates were complex compounds comprising TiN precipitate of square shape as core with Nb containing precipitate nucleated on pre-existing TiN precipitate as caps on one or more faces at high temperatures. The fine and spherical Nb carbides and/or carbonitrides precipitated heterogeneously on dislocations and sub-boundaries at low temperatures. The thermomechanically controlled processing promoted the precipitation of the secondary phase particles.

关 键 词：析出 管线钢 针状铁素体 控轧控冷 

分 类 号：TG142.1[一般工业技术—材料科学与工程]