CSP线高强度细晶热轧板的混晶和变形拉长晶粒的成因

对CSP线生产的高强度细晶热轧板的混晶和拉长晶粒的成因进行了分析，用有限元分析法模拟了热轧带钢的变形区的剪切应变场和温度场，用Gleeble实际模拟轧制工艺和组织变化。结果表明，CSP线高强度细晶热轧板的混晶和拉长晶粒的形成与钢板轧制过程中的钢板表层的变形场及温度场有关，也与先析出铁素体的形成后再进行轧制变形的过程有关；采用奥氏体深过冷轧制，既保证得到细晶粒又避免产生混晶和被变形拉长的晶粒。新的CSP轧制工艺，成功地生产了高强度高成形性细晶粒C-Mn热轧板。

Formation of Mixed Grain and Deformed Elongated Grain of High Strength Fine Grain Steel Strip Produced on CSP Line

The formation of mixed grain and deformed elongated grain of high strength, fine grain hot rolled strip produced by CSP line is investigated The shear strain field and temperature field in deformation area were simulated by FEA (finite element analysis) method the rolling technology and structure variation during rolling and cooling were simulated by Gleeble test The results showed that the formation of mixed and deformed elongated grain in hot rolled strip are mainly related with the strain field and temperature field in the surface layer of strip, and the deformation after formation of proeutectoid ferrite The deep undercooling rolling of austenite was suggested to eliminate such unfavorable structure Based on the relative testing results, a new rolling technology on CSP line was designed and put into operation, the fine grain steel C Mn hot rolled strip with high strength and good formability have been successfully produced