【摘要】 通过阴极极化曲线的测定研究了硫酸盐电解液喷射速度u(流速 )对阴极过电位 ηC 和沉积层晶粒尺寸的影响。结果表明 ,电解液流速增大 ,有利于氢还原析出 ,导致过电位显著增大 ,晶粒尺寸减小。当电流密度为 14 0A/dm2 时 ,喷射速度由 0 .83m/s增大到 5 .0 0m/s,阴极过电位从 1.4 8V增至 8.5 2V ;晶粒尺寸从 2 2 .6nm减小到18.9nm。随电流密度增大 ,阴极上析氢步骤逐渐取代水合镍离子电化学还原步骤并成为整个过程的控制步骤更多还原

【Abstract】 Effects of jet flow rate on the cathodic overpotential and grain size of deposit were studied by measuring cathodic polarization curve in sulfate system.The results show that cathodic overpotential increases obviously with jet flow rate increasing because of hydrogen evolution,while grain size becomes fine.When current density is 140A/dm²,overpotential increases from 1.48 V to 8.52 V and the grain size decreases from 22.6 nm to 18.9 nm with jet flow rate increases from 0.83 m/s to 5.00 m/s.Hydrogen evolution on cathode becomes the control step of whole electrochemical process gradually substituting the electrochemistry deoxidization of Ni²⁺·mH₂O with increase of current density.更多还原