【摘要】 利用双槽电沉积法制备组分调制Ni/Cr多层膜,探讨了Ni/Cr多层膜的合金化特性。借助SEM和EDS对Ni-Cr合金覆盖层的表面形貌、微观结构以及化学组成进行了表征。结果表明,减小周期厚度,提高热处理温度,延长保温时间有助于提高多层膜的合金化程度。经高温处理后,Ni-Cr合金覆盖层化学组分均一,与理论值基本吻合;其微观形貌由原来的结节状或颗粒状结构转变为块状结构,并且未产生热应力开裂等现象。与相同厚度的镍镀层和铬镀层比较,Ni-Cr合金覆盖层具有更好的耐腐蚀性能。更多还原

【Abstract】 Ni-Cr alloy coatings were prepared via a two-step process, namely Ni/Cr multilayered films of thickness modulation were firstly prepared by dual bath technique, which then subjected to alloying treatment at proper elevated temperature. The microstructure and chemical composition of Ni-Cr alloy coatings were characterized by means of SEM and EDS. The results show that with the decreasing period of modulation as well as the increasing heat-treatment temperature and time, the alloying process for Ni/Cr multilayered films could be expediently realized. After high temperature treatment, the chemical composition of the Ni-Cr alloy coatings is homogeneous on average, which is basically consistent with the theoretical value. Of which the surface morphology changes from the original nodular-or granular-like structure to block-like structure, while no thermal stress cracking is observed. Besides, their corrosion resistance was evaluated in comparison with nickel coating and chromium coating of the same thickness. It is found that the Ni-Cr alloy coatings have better corrosion resistance.更多还原