【作者】 程四华； 周玉丽； 邸全康； 王勇； 王立峰；

【Author】 CHENG sihua ZHOU Yuli DI Quankang Wang Yong Wang Lifeng (Shougang Research Institute of Technology Beijing 100043)

【机构】 首钢技术研究院；

【摘要】 本文主要研究了表层超快冷工艺下（SUFC）830MPa级高强精轧螺纹钢筋碳氮化物析出形态与析出强化方式。结果表明,高强精轧螺纹钢筋析出相有方形、球形和片状三种形态,析出相结构基本相同,均为（Ti、V₁、）（CN）。钢筋芯部析出物较多,细小、弥散,成片状或细片状,尺寸主要集中在10～30nm;边部析出物相对较少,成片状或方、球形,尺寸在100nm以内。表层超快冷工艺下高强精轧螺纹钢筋具有典型组织特征:边部回火索氏体,芯部铁素体+珠光体,在组织强化的基础上通过弥散析出、相间析出和铁素体基体中位错线上析出等析出强化方式,弥补部分芯部软相和边部过冷强化相的强度差异,保证了轧材的性能稳定。更多还原

【Abstract】 This paper mainly studies precipitation forms and precipitation strength modes of carbonnitrides for 830 MPa high-strength finished twisted steel bar during surface ultra fast cooling process.The results show that precipitation phase have three forms that is square,sphere and flake,and the structures are all (Ti_xV_1-x)（CN）.Core educts of high-strength finished twisted steel bar are more,disperse and fine,the forms are flaky/fine flaky,and the size is almost between 10nm and 30nm;For edge educts are relative less, square/sphere,and sizes is iner 100nm;Typical organization characteristics are the core is tempered sorbite and the edge is ferrite and pearlite,make use of dispersion precipitation,interphase precipitation and the precipitation on dislocation line inner ferrite on the basis of structure strengthening,make up for strength differences between the region and the core,ensuring the stability of high strength finished twisted steel bar.更多还原