摘要
通过改变镀液中H_3PO_3的添加量(15~40 g/L)制备不同P含量的Fe-Co-Ni-P镀层,采用XRD衍射仪、交流阻抗谱和超声波气蚀试验,分别研究和分析了P含量对镀层的结构以及腐蚀、气蚀性能的影响。结果表明:该四元合金镀层基本都为非晶态。随着合金镀层中P含量增加,镀层表面的胞状组织越来越细密,其耐腐蚀性能逐渐增强。当镀液中H_3PO_3添加量为40 g/L时,镀层的耐腐蚀性能最好。当镀液中H_3PO_3为15 g/L时,交流阻抗谱表现出Warburg阻抗的特征,溶液状态由电荷迁移、扩散以及化学反应混合。当镀液中H_3PO_3为20~40 g/L时,镀层的交流阻抗谱都只有一个容抗弧,表现出一个时间常数特征,且电极过程存在扩散受阻的现象。当镀液中H_3PO_3为40 g/L时,拟合的等效电路中的镀层电荷转移电阻Rf达到最大值3 494Ω?cm^2。且当镀液中H_3PO_3的添加量为40 g/L时,其镀层抗气蚀性能也最好。
Fe-Co-Ni-P alloy coatings with different P content were prepared by adjusting the amount of H3PO3(15-40 g/L) in the bath. The influence of P content on the structure and properties of the electrodeposited Fe-Co-Ni-P alloy coating was analyzed by XRD, AC impedance spectra and ultrasonic cavitation test. The results show that these alloyed coatings are amorphous. Higher P content is benificial to refine the cellular structure of coatings, which helps to improve the corrosion resistance of the coating. When the H3PO3 content in the bath is to 40 g/L, the coating has the best corrosion resistance. When the H3PO3 content in the bath is to 15 g/L, the AC impedance spectra show the characteristic of Warburg impedance. However, when the H3PO3 content in the bath is 20-40 g/L, it only have a capacitive arc, which indicates ablocked diffusion in the electrode process. When the H3PO3 content in the bath is to 40 g/L, the charge transfer resistance Rf of the equivalent circuit coating reaches the maximum value 3 494 O.cm2 in all the coatings. Moreover, the coating fabricated from 40 g/L H3PO3 has the best cavitation resistance performance.
作者
罗婵媛
纪秀林
李泽
LUO Chan-yuan JI Xiu-lin LI Ze(College of Mechanical and Electrical Engineering, Hohai University, Changzhou 213022, Jiangsu Engineering Re- search Center of Dredging Technology of Ministry of Education, Hohai University, Changzhou 213022, Jiangsu)
出处
《中国表面工程》
EI
CAS
CSCD
北大核心
2017年第2期92-97,共6页
China Surface Engineering
基金
国家自然科学基金(51475140)~~
关键词
电沉积
电镀
极化曲线
交流阻抗谱
气蚀
electrodeposition
electroplate
polarization curve
AC impedance spectroscopy
cavitation