表面技术2017，Vol.46Issue(2)：92-97,6.DOI:10.16490/j.cnki.issn.1001-3660.2017.02.014
电沉积Cr-WO3纳米复合镀层及其性能研究
Electrodepositing Cr-WO3 Nano-composite Coating and Its Performance Evaluation
摘要
Abstract
The work aims to improve corrosion resistance and thermal stability of chromium coating on low carbon steel. Nano WO3 particles were dispersed in chromium plating bath, and the Cr-WO3 nano composite coating was electrodeposited by direct-current electrodeposition from citric acid-sulfate bath. Then surface microtopography of the coating was observed by me-tallographic microscope and X-ray diffractometer (XRD), and phase structure of the coating was tested. Hardness and corrosion resistance of the Cr-WO3 nano composite coating were evaluated by virtue of Vickers hardness test, polarization curve and elec-trochemical impedance test. Lamellar grain structure was present on the surfaces of Cr coating and Cr-WO3 nano composite coating, the grain size of Cr-WO3 nano composite coating was smaller than that of Cr coating. Electrochemical testing was per-formed in 5wt.% NaCl solution. Compared with the Cr coating, corrosion current density (Jcor) of Cr-WO3 nano-composite coating decreased to 0.38μA/cm2, electrochemical impendence increased, electrochemical activity was lower and corrosion re-sistance was better. The hardness of Cr-WO3 nano-composite coating was close to that of Cr coating. Addition of Cr-WO3 did not contribute to higher hardness, but it could prevent presence and expansion of cracks on the coating during annealing, and reduce changes of coating surface states. Cr-WO3 particles could be mixed in the coating effectively to reduce grain size of the coating. The lower electrochemical activity of the Cr-WO3 nano-composite coating is, the better the corrosion resistance will be. WO3 nano has minor influence on the hardness of unannealed coating. However, it can reduce the value of amplitude of an-nealed coating and improve its thermal stability.关键词
电沉积/复合镀层/WO3/耐蚀性/镀铬/电化学阻抗/硬度Key words
electrodeposition/composite coating/WO3/corrosion resistance/chroming/electrochemical impedance/hard-ness分类
矿业与冶金引用本文复制引用
王毅..电沉积Cr-WO3纳米复合镀层及其性能研究[J].表面技术,2017,46(2):92-97,6.基金项目
江西省自然科学基金(20151BAB216012)Suported by Natural Science Foundation of Jiangxi Province(20151BAB216012) （20151BAB216012）
