电沉积法制备镍与镧、铈的非晶态合金及其晶化动力学

稀土元素(La、Ce)的标准还原电位较负,在水溶液中很难电沉积出来.通过选用合适的络合剂和工艺条件制备出Ni-La、Ni-La-P、Ni-Ce、Ni-Ce-P以及Ni-P合金,除Ni-Ce外,均具有非晶态的结构;并对这几种非晶态合金进行了晶化动力学研究,用差示扫描量热法(DSC)测定了它们的晶化活化能以及所遵守的动力学方程.

Preparation of Amerphous Alloys of Nickel with Lanthanum, Cerium by Electrodepositionand Crystallization Kinetics

Rare-earth elements (La,Ce) have lower standard equilibrium potentials than that of hydrogen and are very difficult to electrodeposite from aqueous solution. Ni-La,Ni-La-P,Ni-Ce,Ni-Ce-P and Ni-P alloys deposits were obtained from aqueous solutions by using optimized electroplaing solutions and process conditions. The experimental results show that these alloys (except Ni-Ce) have amorphous structure. The crystallization kinetics of these amorphous alloy coatings were investigated. The crystallization activation energy and kinetic equation of four kinds of amorphous coatings have been determined by DSC method.The results indicate that the crystallization activation energy of Ni-P,Ni-La,Ni-La-P,Ni-Ce-P amorphous coatings are 200.3,360.8,517.7,420.5 kJ?mol－1 respectively.The crystallization kinetics of the four kinds of amorphous coatings may be expressed by the following equation: