热轧变形量对含铌低Si-Mn系双相钢组织与性能的影响

Effect of Hot Rolled Deformation on the Microstructure and Mechanical Property of Low Si-Mn-Nb As-hot Dual-Phase Steel

采用TEM、SEM技术和光学显微分析等方法,研究了不同变形量对热轧Si-Mn系双相钢组织与力学性能的影响。试验结果表明,组织形貌为岛状的马氏体弥散分布在细小的铁素体基体中,可以使热轧双相钢获得良好的综合机械性能。随着变形量的增加,第二相的体积分数增加,但第二相随着变形量增加严重偏析,且热轧双相钢的屈服强度和抗拉强度先增加后降低、屈强比升高、塑性降低。综合分析表明,当变形量为92.1%时,抗拉强度平均达到795.66 MPa,力学性能最佳。

The effect of different deformation on the microstructure and mechanical property of Si-Mn-Nb ashot dual-phase steel were investigated by using TEM,SEM technology and optical microscopy. The results showed that the structure morphology where the island of martensite are dispersed in small ferrite matrix enables hot rolled dual phase steel to obtains comprehensive mechanical properties.With the increase of the deformation,the volume of the second phase increases,but some second-phase particles is serious segregation.The yield strength and tensile strength of hot rolled dual phase steel firstly increase and then drop,yield ratio increased and plasticity decrease.It is found out that the deformation of 92.1% can result in excellent combined mechanical performance with tensile strength achieving an average of 795.66 MPa.