连续柱状晶组织BFe10-1-1合金的电化学腐蚀性能  

Electrochemical corrosion performance of continuous columnar-grained BFe10-1-1 alloy

作　　者：甘春雷[1] 刘雪峰[1] 黄海友[1] 谢建新[1] 

机构地区：[1]北京科技大学材料先进制备技术教育部重点实验室,北京100083

出　　处：《北京科技大学学报》2011年第12期1492-1500,共9页Journal of University of Science and Technology Beijing

基　　金：国家自然科学基金资助项目(50674008);国家科技支撑计划资助项目(2011BAE23B00);中央高校基本科研业务费资助项目(FRF-TP-10-002B);国家重点基础研究发展计划资助项目(2011CB606300)

摘　　要：采用线性极化、电化学阻抗谱等电化学方法研究了连续柱状晶组织BFe10-1-1合金在3.5%(质量分数)NaCl溶液中的耐蚀性能,并与普通铸造多晶组织BFe10-1-1合金进行了对比.极化曲线测试结果表明,两种合金具有相似的电化学行为,极化曲线都包括活性溶解区、活化-钝化转变区和极限电流区,但连续柱状晶组织合金腐蚀速率小于普通铸造多晶组织合金,主要是由于连续柱状晶组织BFe10-1-1合金的微观偏析程度较小,能有效避免枝晶间局部腐蚀的发生.电化学阻抗谱测试结果也表明,该合金的电荷传递电阻和腐蚀产物膜电阻均大于普通铸造多晶组织合金,具有更高的耐蚀性.The corrosion resistance of BFe10-1-1 alloy with continuous columnar-grained microstructure in a 3.5% NaCl solution was investigated by means of polarization tests and electrochemical impedance spectroscopy（EIS）,and compared with that of BFe10-1-1 alloy with conventional polycrystalline microstructure fabricated by conventional casting.Polarization test results show that both BFe10-1-1 alloys have similar electrochemical behavior,and their polarization curves include three distinct regions,that is,the active dissolution region,the active-passive transition region and the limiting current region.However the corrosion rate of BFe10-1-1 alloy with continuous columnar-grained microstructure is lower than that of the one with conventional polycrystalline microstructure,as less microsegregation in BFe10-1-1 alloy with continuous columnar-grained microstructure can effectively avoid interdendritic corrosion.EIS spectra indicate that BFe10-1-1 alloy with continuous columnar-grained microstructure has a higher charge transfer resistance and a higher corrosion product film resistance compared with BFe10-1-1 alloy with conventional polycrystalline microstructure.The results further demonstrate that BFe10-1-1 alloy with continuous columnar-grained microstructure has a better corrosion resistance.

关 键 词：铜镍合金 定向凝固 显微组织 偏析 耐蚀性 

分 类 号：TG113.23[金属学及工艺—物理冶金] TG146.1[金属学及工艺—金属学]