一种低合金低温铸钢及其组织与性能  

Composition Design of Low Alloy Cryogenic Cast Steel with Analysis of Microstructure and Mechanical Properties

作　　者：陈威[1] 高义民[1] 邢建东[1] 王必辉[1] 汪勇[1] 梁龙[1] 

机构地区：[1]西安交通大学金属材料强度国家重点实验室,西安710049

出　　处：《西安交通大学学报》2008年第7期875-879,共5页Journal of Xi'an Jiaotong University

摘　　要：针对极地石油钻机用大钩对材料的性能要求,设计了一种含Cr、Ni低合金低温铸钢,考察了不同热处理工艺对材料组织、室温力学性能以及低温冲击韧性的影响.采用扫描电镜、X射线衍射和透射电镜等手段分析了低温铸钢试样的微观结构、相组成及断口形貌.结果表明:该低温铸钢经930℃炉冷+920℃油冷+680℃空冷热处理后,其显微组织为回火索氏体,其中铁素体呈等轴状,渗碳体已趋于团球化;-20℃冲击功达到57 J,冲击断裂机制为韧性断裂,-45℃冲击功为32 J,冲击断裂机制为不完全脆性断裂.在此热处理条件下,低温铸钢试样表现出优良的室温综合力学性能和较高的低温冲击韧性,达到了石油钻机用大钩所要求的材质性能.According to the performance requirements of polar oil-drilling rig, a nickel and chromium-containing low alloy cryogenic cast steel （NCCS） was designed. The influences of heat treatment on microstructure, room-temperature mechanical properties and cryogenic impact toughness were studied. Scanning electron microscopy, X-ray diffraction and transmission electron microscopy were utilized respectively to analyze the microstructure, phase composition and impact fracture. The NCCS undergone the heat treatment of annealing （930 ℃）, quenching （920 ℃） and tempering （680℃） belongs to sorbitic cast steel with excellent mechanical properties and cryogenic impact toughness to meet the design requirements of oil-drilling rig.

关 键 词：低温铸钢 回火索氏体 低温冲击韧性 石油钻机 

分 类 号：TG142[一般工业技术—材料科学与工程]