镀液pH值对化学镀Co-Ni-P合金镀层结构的影响

用 PHS- ZC酸度计、TG32 8A电光分析天平、ASM- SX电子探针、H- 80 0透射电镜和Dmax/ RB旋转阳极 X射线衍射仪测定和分析了化学镀 Co- Ni- P合金镀液的 p H值、镀层的沉积速度、成分和结构。结果表明 ,镀液的 p H值对镀层结构影响的实质是改变了镀层的化学成分 ,尤其是磷含量。p H值越低 ,沉积速度越慢 ,镀层的钴含量越低、镍和磷的含量越高 ,越容易形成非晶态镀层。随 p H值升高 ,镀层的晶化趋势越大 ,并向微晶和晶态转化。

EFFECT OF pH VALUE OF PLATING BATH ON STRUCTURE OF ELECTROLESS PLATED Co-Ni-P ALLOY COATING

The pH value of plating bath and the deposit rate,compositions and structure of electroless deposited Co Ni P alloy coating were determined and analyzed by PHS ZC acidity meter,TG328A analytical balance,ASM SX electron microprobe,H 800 transmission electron microscope and Dmax/RB rotationary anode X diffractometer.The results showed that,the essence of the effect of pH value of plating bath on structure of electroless deposited Co Ni P alloy coating was that the compositions and the phosphorus content of the coating was changed.The lower the pH value of plating bath,the slower the deposit rate of the coating,the lower the cobalt content of the coating,the higher the nickel and phosphorus content of the coating,and the more easily the amorphous coating forms.As pH value of plating was increased,crystallizing tendency of the coating was obvious and structure of the coating was transformed into crystallite and crystalline state.