脉冲电沉积Ni-Al_2O_3纳米复合镀层晶体结构的变化

Variation of crystalline structure of pulse electroplated Ni-Al_2O_3 nano composite coating

用直流电镀法制备了纯Ni镀层和Ni-Al2O3纳米复合镀层,并采用双脉冲电镀电源制备了Ni-Al2O3纳米复合镀层。通过扫描电镜观察了镀层的表面微观形貌,用X射线衍射仪分析了镀层的微观晶体结构,探讨了Al2O3微粒对镀层的沉积和生长过程的影响。结果表明,纳米Al2O3颗粒的加入使镍镀层的晶体择优取向发生改变,晶粒细化。双脉冲电镀电源的引入使晶格点阵常数变大,晶格畸变增大,进一步细化了镀层的晶粒。

The pure nickel coating and Ni-Al2O3 nano composite coating were prepared by direct current electroplating and the another Ni-Al2O3 nano composite coating was prepared by dipulse electroplating. The surface morphologies of the coatings were observed by scanning electron microscope and the crystal structures of the coatings were tested and analyzed by X-ray diffractometer. The effect of Al2O3 particles addition on the deposit process and the coating growth kinetics were discussed. The results show that introduced Al2O3 nano-particles will change the preferential orientation of the matrix Ni and refine the crystalline grains. The lattice constants and lattice distortion of the dipulse electroplated coating were increased and the crystalline grains are further refined.