硼氢化钠对滑轮用铸钢板化学镀Ni-B合金薄膜性能的影响

在滑轮用铸钢板上化学镀Ni-B合金薄膜,并研究了硼氢化钠的质量浓度对化学镀Ni-B合金薄膜性能的影响。结果表明:适当增加硼氢化钠的质量浓度,有利于增大化学镀Ni-B合金薄膜的厚度及硼的质量分数,从而提高化学镀Ni-B合金薄膜的硬度。当硼氢化钠的质量浓度大于1.2 g/L时,硼氢化钠的水解速率加快及剧烈的析氢反应,导致化学镀Ni-B合金薄膜的厚度及硬度有所降低。当硼氢化钠的质量浓度为1.2 g/L时,化学镀Ni-B合金薄膜表面"胞状"颗粒均匀、致密,摩擦因数和磨损率最低,具有最佳的耐磨性。

Effect of Sodium Borohydride on Properties of Electroless Ni-B Alloy Thin Film on Cast Steel Plate Used for Pulley

Electroless Ni-B alloy thin film was prepared on the surface of cast steel plate used for pulley,and the mass concentration of sodium boro hydride on the properties of electroless Ni-B alloy thin film was studied.The results showed that increasing the mass concentration of sodium borohydride was beneficial to improve the thickness of electroless Ni-B alloy thin film and the mass fraction of boron in the thin film resulting in the improvement of hardness.When the mass concentration of sodium borohydride was greater than 1.2 g/L,the thickness and hardness of electroless Ni-B alloy thin film were reduced due to the accelerated hydrolysis rate of sodium borohydride and violent hydrogen evolution reaction.When the mass concentration of sodium borohydride was 1.2 g/L,the electroless Ni-B alloy thin film showed uniform and dense cellular morphology,and possessed excellent resistance with the lowest friction coefficient and wear rate.