铌微合金化高强船板钢z向性能不合原因分析  

Analysis of reasons for the unqualified z- direction properties of Nb-bearing high strength ship plate steels

作　　者：王小勇[1] 狄国标[1] 杨永达[1] 王彦锋[1] 麻庆申[1] 

机构地区：[1]首钢技术研究院宽厚板所,北京100043

出　　处：《钢铁》2015年第10期85-89,95,共6页Iron and Steel

摘　　要：对铌微合金化高强船板钢z向性能不合的原因进行了分析。借助光学显微镜、扫描电镜对试验钢的组织及z向拉伸断口进行了观察,并通过Thermo-Calc软件及固溶度积公式对Nb C的全固溶温度进行了计算,结果表明:聚集分布的大块富铌析出物及长条状Mn S是导致试验钢z向性能不合的重要原因;虽然提高加热温度有利于富铌析出物的回溶,但常规的轧制加热也很难消除大块富铌析出物对钢板的z向性能的不利影响。The reason for the unqualified z- direction properties of the Nb-bearing high strength ship plate steels was analyzed. The microstructures and z- direction tensile fracture samples were observed by optical microscope（OM） and scanning electron microscope（SEM） and the solid dissolved temperature of Nb C in the steel was calculated according to the Thermo- Calc software and the solubility expression of Nb C in austenite. The results showed that gathered precipitates with Nb and trip-liked sulfide inclusions（Mn S） were the main reason for the unqualified z- direction properties of the tested steels. While the increase of heating temperature is advantageous to dissolve the precipitates with Nb,the conventional rolling heating is hard to eliminate the adverse effects of large precipitates on the z- direction properties of the steel.

关 键 词：含铌钢 高强船板 Z向性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]