Fe基非晶合金的晶化及其在NaCl溶液中的电化学腐蚀行为

Crystallization and electrochemical corrosion behaviors of amorphous Fe-based alloys in NaCl solution

采用单辊甩带法制备出完全非晶态的Fe78Si13B9和Fe73.5Si13.5B9Nb3Cu1薄带,并利用非晶晶化退火法制备非晶和纳米晶双相合金Fe73.5Si13.5B9Nb3Cu1薄带。利用X射线衍射仪和示差扫描量热计对该非晶薄带的非晶特性及其晶化过程进行研究,并用电化学极化曲线的方法和电化学阻抗技术对比研究非晶Fe78Si13B9和双相合金Fe73.5Si13.5B9Nb3Cu1在1mol/LNaCl溶液里的电化学腐蚀行为,用SEM对极化测试后的试样形貌进行观察;同时还研究不同的热处理温度对材料的结构及在1mol/LNaCl溶液里耐腐蚀性能的影响。结果表明:该非晶薄带的晶化过程分为两步;双相合金比非晶合金的耐腐蚀性要好;随着热处理温度升高,非晶合金和双相合金的耐腐蚀性能都得到提高。

Amorphous ribbons of Fe78Si13B9 and Fe73.5Si13.5B9Nb3Cu1 were prepared by the single-roller melt-spinning process, and the ribbons of amorphous and nano-crystalline two-phase Fe73.5Si13.5B9Nb3Cu1 alloys were obtained by annealing. The amorphous ribbons and their crystallization processes were identified by differential scanning calorimeter and X-ray diffraction. A comparative study of the electrochemical corrosion behaviors of amorphous Fe78Sij3B9 and two-phase Fe73.sSi13.sB9Nb3Cul alloys was performed by the linear polarization method and electrochemical impedance spectroscopy （EIS） in 1 mol/L NaC1 solution. The morphologies of the samples after potentiodynamic polarization were observed by SEM. The influence of heat treatment at different temperatures on the alloy structure and corrosion resistance in lmol/L NaCl solutions was investigated. The results show that the crystallization process of the amorphous ribbons can be divided into two steps, and the two-phase alloy has a higher corrosion resistance than the amorphous alloy. The corrosion resistances of the amorphous and two-phase alloys increase as the thermal treatment temperature rises.