低温Hi-B钢全流程组织和织构演变规律研究

Study on Evolution Laws of Microstructure and Texture in Whole Process of Low Temperature Hi-B Steel

采用金相显微镜和X射线衍射仪(XRD)观察低温Hi-B钢连铸坯和经热轧、常化、冷轧、脱碳退火、高温退火工序后钢板的金相组织和织构,分析全流程组织和织构的演变规律。结果表明,连铸坯低倍组织以柱状晶为主,中心等轴晶区比例为7%~12%;热轧板组织由铁素体和珠光体交替的带状组织组成;常化酸洗板组织由细晶带和再结晶组织组成。热轧板和常化板厚度1/8处织构以Goss织构和黄铜织构为主,钢板经过高温退火发生二次再结晶形成强Goss织构。

In this paper,the continuous casting billet of low temperature Hi-B steel,metallographic structure and texture of plates after such processes as hot rolling,normalizing,cold rolling,decarburizing annealing and high temperature annealing are observed with metallographic microscope and X-ray diffractometer(XRD)as well as the evolution laws of microstructure and texture in the whole process are analyzed.The results showed that the macrostructure of continuous casting billet was mainly columnar crystal and proportion of equiaxed crystal zone was 7%~12%;microstructure of hot rolled plate was composed of alternant banded structure of ferrite and pearlite;microstructure of normalized pickled plate was composed of fine crystal zone and recrystal microstructure.The textures at 1/8 of thickness of hot rolled plate and normalized plate are mainly Goss texture and brass texture as well as strong Goss texture is formed with the secondary recrystallization after high temperature annealing.