不同成分体系对超低碳烘烤硬化钢性能的影响

研究了不同成分体系超低碳烘烤硬化钢的性能特征,生产结果表明:Ti-BH钢屈服强度和BH值较低,伸长率和"值富裕量较大,并且BH值波动较大.通过对不同成分体系钢板的微合金化原理进行分析,确定了不同成分体系烘烤硬化钢性能不同的原因,并据此将烘烤硬化钢的成分体系由Ti-ULC改为Nb+Ti复合体系.更改后的烘烤硬化钢性能指标...

Effect of chemical composition of extra low carbon bake hardening steel on its properties

The features of extra low carbon bake hardening steel with different chemical compositions are studied in this paper.The result shows that the yield strength and BH value of Ti-BH are low and the elongation percentage and n-value are lager than the technical specification.The BH value fluctuates relatively lager.Based on the analysis of microalloying theory for different series of BH steel sheets,the causes that BH steels with different chemical compositions vary in properties are ascertained.On this basis,the Ti-ULC BH steel is amended to Nb-Ti-ULC BH steel.The mechanical properties of amended BH steel satisfy the technical specification absolutely and the stability of BH value is improved greatly.The aging experiment shows that the BH steel has excellent aging behavior and achieves the balance between bake hardening behavior and aging behavior at room temperature.