材料期刊网

通过真空冶炼、锻造、热轧和不同固溶处理温度试验制备出含有不同微合金元素含量的445M铁素体不锈钢,结合其冲击试验,运用金相显微镜、扫描电子显微镜及能谱仪等分析方法,探讨了微合金化对其韧性的影响。结果表明：化学元素铌和钛的加入,在晶粒内部和晶界上形成了TiN、NbC和（Nb,Ti）（C,N）析出相,稳定了钢中的碳、氮元素,防止由铬的碳氮化物析出而引起的晶间腐蚀,但对钢的冲击韧性有一定影响。采用单铌作为稳定化元素钢的冲击韧性优于单钛稳定钢;添加少量的钛,采用Nb＋Ti双稳定钢,也可获得优异的冲击韧性,并且能够降低生产成本。

The 445M ferritic stainless steel with different micro-alloy element content was prepared through the process of vacuum smelting, forging, hot rolling and test under different solid solution temperature. The effect of microalloy on toughness of the 445M ferritic stainless steel was investigated through metallographic microscope, scanning electronic microscope and energy spectrometer. The results show that： with adding the Nb and Ti, the precipitated phase of TiN, NbC, （Nb,Ti） and （C, N） will be generated in the inner and boundary of grain, the content of C, N can be stabled and the inter-granular corrosion which is generated by the exhalation of the carboni- trides can be prevented from. However, the impact toughness of the steel will be influenced. And it can be found that the impact toughness of the Nb stable steel is better than that of the Ti stable steel, however, the excellent impact toughness can be obtained with adding a small amount of Ti and reducing the content of the Nb, and the cost of production also can be reduced.