轻量化车轮钢590CL的开发与应用

Development and Application of Light Weight Wheel Steel 590CL

通过在碳锰钢中添加微合金元素铌和钛以及利用控轧控冷工艺在首钢京唐公司2250热连轧生产线上成功开发出600MPa级轻量化汽车车轮轮辋用钢590CL。金相组织观察与统计结果表明，试验钢铁素体晶粒平均尺寸为4．52μm，沉淀析出的（N1），Ti）（C，N）复合析出物的平均直径约为4．84nm，体积分数平均值为2．39×10^-4。经过理论计算，细晶强化对屈服强度的增量约为259MPa，第二相粒子析出强化对屈服强度的增量约为71MPa。试验结果表明，试验钢具有良好的焊接性能和成形性能，经国内某大型车轮厂试用，试验钢闪光对焊后成形合格率达到98％以上，车轮径向疲劳寿命达到125万次。

Light weight auto wheel rim steel 590CL with the tensile strength of 600 MPa was developed successfully on the Shougang Jingtang Company 2250 Hot-rolling line under the way of adding microalloys Ni and Ti in carbon menganese steel, as well as using TMCP process. Microstructure observation and statistics showed that the ferrite average grain size of test steel was 4.52 μm, the average diameter of （Nb, Ti） （C, N） composite precipitate was 4. 84 nm and the volume fraction was 0. 023 9%. Through theoretical calculation, the contributions of grain refinement strengthening and precipitation strengthening to yield strength were about 259 MPa and 71 MPa, respectively. The results also showed that this test steel had excellent weldability and forming properties. The success rate of forming after flash butt welding was 98% , while the life of radial fatigue test was 1.25 million cycles when the test steel was used in a certain famous wheel factory.