论文部分内容阅读
设计了两种低成本的铁素体/贝氏体双相钢,通过光学显微镜、扫描电镜和拉伸试验机研究了不同Si含量对试验钢组织与性能的影响,研究了试验钢在扩孔过程中的裂纹形成及扩展行为。结果表明,通过合理控轧控冷技术,能够获得780 MPa以上抗拉强度,伸长率大于17%,综合性能良好的试验钢;随着Si含量的增加,试验钢的屈服强度和抗拉强度显著提高,但是伸长率和扩孔性能有所下降;本试验钢的裂纹扩展机制为微孔聚集模式。
Two kinds of low-cost ferrite / bainite dual-phase steels were designed. The effects of different Si contents on the microstructure and properties of the test steels were studied by optical microscope, scanning electron microscopy and tensile testing machine. Crack formation and spreading behavior in the process. The results show that the controllable rolling and controlled cooling technology can obtain the test steel with tensile strength above 780 MPa, elongation greater than 17% and good overall performance. With the increase of Si content, the yield strength and tensile strength Significantly increased, but the elongation and hole expansion performance decreased; crack propagation mechanism of the experimental steel micropore aggregation mode.