ABSTRACT

The effect of Ti addition on the microstructure and corrosion resistance of the as-cast Ti-stabilised Fe–17Cr ferritic stainless steels was investigated by optical microscopy, scanning electron microscopy, X-ray diffraction and energy-dispersive spectrometer. The corrosion behaviour of the as-cast Fe–17Cr ferritic stainless steel in 10 wt-% HNO₃ and 10 wt-% NaOH solutions was examined by using potentiodynamic polarisation curves and electrochemical impedance spectroscopy. After Ti addition from 0.06 to 0.26 wt-%, the size of TiN precipitates in the as-cast Fe–17Cr ferritic stainless steel increases and the corrosion resistance is improved in 10 wt-% HNO₃ and 10 wt-% NaOH solutions, especially in 10 wt-% HNO₃ solution. Mott–Schottky curves demonstrate that the addition of Ti can inhibit the decomposition of the passive film, which can improve corrosion resistance.

摘要

通过光学显微镜，扫描电子显微镜，X射线衍射和能谱仪研究了添加Ti对铸态的Ti稳定化Fe-17Cr铁素体不锈钢的组织和耐蚀性的影响。通过使用电位动力学极化曲线和电化学阻抗谱，检查了铸态的Fe-17Cr铁素体不锈钢在10 wt％HNO ₃和10 wt％NaOH溶液中的腐蚀行为。在添加0.06至0.26 wt％的Ti后，铸态的Fe–17Cr铁素体不锈钢中TiN的沉淀物增加，并且在10 wt％的HNO ₃和10 wt％的NaOH溶液中，耐蚀性得到改善。在10 wt％HNO _3中解决方案。Mott–Schottky曲线表明，添加Ti可以抑制钝化膜的分解，从而可以提高耐蚀性。