纳米ZrO2微粒对电沉积Ni基复合镀层性能的影响

Effects of ZrO2 nanoparticle on properties of Ni-based composite coating prepared by electrodeposition

在磁场-超声复合作用下,用脉冲电沉积方法,在黄铜基体表面制备Ni-ZrO2复合镀层,研究镀层的显微组织、结合力和耐腐蚀性能。结果表明:加入纳米ZrO2微粒,提供更多的异质成核点,使复合镀层表面均匀致密、晶粒细化。纳米粒子添加量为10 g/L时,复合镀层晶面择优取向被抑制,晶粒生长趋于各向同性;晶粒尺寸和显微硬度分别为17.98 nm和417HV,较纯镍镀层的晶粒尺寸减小9.42%,显微硬度提高17.13%;复合镀层结合力最大,为1913.2 MPa;极化曲线和阻抗曲线都表明复合镀层具有最好的耐腐蚀性。

Ni-ZrO2 composite coatings were prepared on the surface of Cu substrate by pulse electrodeposition under magneticultrasonic compound fields.The microstructure,binding force and corrosion resistance of the composite coatings were investigated.The results show that Ni-ZrO2 composite coating displays a homogeneous and compact surface with refinement grains due to ZrO2 particles serving as more heterogeneous nucleation cores.When ZrO2 concentration is 10 g/L,the preferred crystal orientation of the coating is inhibited and the grain growth approaches isotropy.The crystalline size and microhardness of composite coating are 17.97 nm and 417 HV,respectively,which are 9.42%smaller and 17.13%higher than that of the pure Ni coatings.And the composite coating shows the strongest binding force of 1913.2 MPa.Both the cathodic polarization curves and nyquist impedance plots show a fact that the composite coating had best corrosion resistance.