成分对经济型热轧双相钢性能的影响研究

Effect of Chemical Composition on Economical Hot-rolled DP Steel's Properties

在试验室研究了不添加贵重合金元素的经济型热轧铁素体—马氏体双相(DP)钢的成分对组织力学性能的影响。结果表明:添加微量的Nb和Ti元素可提高钢的抗拉强度,同时也可提高钢的屈服强度和屈强比;锰过高或过低都会阻碍组织中马氏体的形成;适当增加硅可以提高钢的抗拉强度并降低延伸率。通过成分控制和配合适当的控轧、控冷工艺可满足DP600和DP800热轧双相钢的性能要求。

The hot rolled DP Steel without expensive alloying elements was studied in the laboratory. The effect of chemical compositions on microstructure and mechanical properties of the hot rolled DP steel was also studied. The resuits show that adding very small amount of niobium and titanium （ microalloying elements） can increase not only the steel＇ s tensile strength, but its yield strength and yield ratio as well. The experiment also shows that adding too much or too little manganese would retard the transformation from austenite to martensite. Adding silicon properly in the steel could increase steel＇ s strength but would reduce its elongation. Performance requirements of steel DP 600 and DP 800 could be met through controlling their compositions with properly controlled rolling and cooling.