摘要
铬镀层具有许多优点,但对环境有严重污染。采用脉冲电沉积方法制备了含22%W,26%W,31%W和36%W的纳米晶Ni-W-Cr-Nd合金层,用作代铬镀层。通过扫描电镜、电子能谱、X射线衍射等对代铬镀层的表面形貌、成分和相结构进行了表征;利用动电位扫描、电化学阻抗技术考察了其耐蚀性能。结果表明:4种W含量的Ni-W-Cr-Nd合金镀层表面均匀致密,无裂纹,晶粒尺寸分别为14,17,21,26 nm;含22%W镀层的抗高温氧化性能和耐蚀性能均优于铬镀层;22%W的镀层400℃热处理后硬度为1 132 HV,磨损失重率为0.018 3mg/(cm2.h),具有较高的硬度和较好的耐磨性。
Four kinds of nanocrystalline Ni-W-Cr-Nd alloy coatings with different tungsten contents,as substitutes for chromium coating,were successfully obtained by pulse electrodeposition.The surface morphology,composition and phase structure of as-deposited alloy coatings were analyzed by means of scanning electron microscopy,energy dispersive spectrometry and X-ray diffraction.The corrosion resistance of the alloy coatings was evaluated using potentiodynamic scan technique and electrochemical impedance spectroscopy.It was found that as-deposited Ni-W-Cr-Nd alloy coatings were dense and uniform,and had no cracks.Grain sizes of the alloy coatings with 22%,26%,31%,36% W were 14,17,21,26 nm respectively.Particularly,the alloy coating with 22% W possessed better high-temperature oxidation resistance and corrosion resistance than Cr coating,and the alloy coating heat-treated at 400 ℃ had a high hardness of 1 132 HV and good wear resistance,showing a small wear rate of 0.018 3 mg/(cm2·h).
出处
《材料保护》
CAS
CSCD
北大核心
2011年第12期1-7,共7页
Materials Protection
基金
桂林理工大学博士基金
关键词
脉冲电沉积
Ni-W—Cr—Nd合金镀层
纳米晶
代铬镀层
镀层性能
pulse electrodeposition
Ni-W-Cr-Nd alloy coating
nanocrystalline
substitute for chromium coating
performance of coating
