锡、铜协同作用下的铁素体不锈钢的冶金行为及腐蚀机理研究

The microstructure of Sn and Cu micro-alloyed ferritic stainless steel will be studied, the dissolution behavior of Sn and Cu in stainless steel melts, and the existence form of which in ferritic stainless steel melts under the conditions of controlled oxygen positions will also be identified by the small crucible and induction furnace thermal simulation experiments. The micro-alloyed theory of Sn and Cu on the ferritic stainless steel can be formed, and the segregation law of Sn and Cu during the solidification process can be gained through the simulation.under the different cooling conditions, at the same time, the mathematical model of solidification segregation will be established, the metallurgical conditions can also be gained on the ferritic stainless steel with low segregation, uniform structure. The effect of the co-action between Sn and Cu on the surface passivating film and its strengthening mechanism to the ferritic stainless steel will be investigated by the distribution analysis of Sn and Cu close to the metal surface layer and the detection to the composition and structure of the surface passivation film. Combining with electrochemical corrosion experiments, the composition of Cr-saving ferritic stainless steel bearing Sn and Cu will be designed, and which can provide a theoretical basis for the Cr-saving ferritic stainless steel development.

通过小坩埚和感应炉热模拟实验，研究锡、铜微合金化铁素体不锈钢的微观结构，查明锡、铜在不锈钢中的溶解行为以及在控制氧位条件下在铁素体不锈钢中的存在形式；形成锡、铜在铁素体不锈钢中微合金化理论，通过不同冷却条件下的模拟实验，掌握锡、铜在不锈钢凝固过程的偏析规律，建立凝固偏析数学模型，得到低偏析、均匀组织结构铁素体不锈钢的冶金条件；通过对贴近金属表面层的锡、铜元素分布分析及表面钝化膜的成分与结构检测，揭示锡、铜协同作用下铁素体不锈钢表面钝化膜的影响及其强化机理，结合电化学腐蚀实验，完成含锡、铜节铬型铁素体不锈钢的合金成分设计，为节铬型铁素体不锈钢开发提供理论依据。

目前，节约资源型铁素体不锈钢的研究越来越受到关注。本项目通过小坩埚和感应炉热模拟实验，研究了锡、铜微合金化铁素体不锈钢的微观结构，查明了锡、铜在不锈钢中的溶解行为以及在控制氧位条件下在铁素体不锈钢中的存在形式；形成了锡、铜在铁素体不锈钢中微合金化理论，掌握了锡、铜在不锈钢凝固过程的偏析规律，建立了凝固偏析数学模型，发现铜、锡易被吸附在稀土夹杂物周围，得到低偏析、均匀组织结构铁素体不锈钢的冶金条件；揭示了锡、铜协同作用下铁素体不锈钢表面钝化膜的强化机理，发现铜的存在可以促进锡的溶解，结合电化学腐蚀实验，完成了含锡、铜节铬型铁素体不锈钢的合金成分设计，同时进行了抗菌性的研究，研究成果为节铬型铁素体不锈钢开发提供理论依据。研究成果应用后，将进一步促进我国不锈钢行业的品种结构优化和技术进步，并显著减少对外贵合金资源依存度，为国家资源节约做出应有贡献。