【摘要】 通过改变化学镀钯液中次磷酸钠的质量浓度，制备了P质量分数分别为4.64%、5.05%、5.71%和6.70%的Pd镀层。采用扫描电镜、能谱仪、X射线衍射仪及电化学工作站分析了P含量对Pd镀层表面形貌、耐蚀性、晶态结构及可焊性的影响。结果表明：随着镀液中次磷酸钠质量浓度的增大，镀层的P质量分数增大，Pd镀层的表面微观形貌和耐蚀性均先改善后变差。当P质量分数为5.71%(即镀液中次磷酸钠的质量浓度为5 g/L)时，Pd镀层的表面形貌和耐蚀性均最佳。所得Pd镀层都是非晶态结构，并且可焊性良好。更多还原

【Abstract】 Pd coatings with different mass fractions(i.e. 4.64%, 5.05%, 5.71%, and 6.70%) of phosphorus were obtained by varying the mass concentration of sodium hypophosphite in an electroless palladium plating bath. The effect of P content of Pd coating on its surface morphology, corrosion resistance, crystal structure, and solderability were studied by scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, and electrochemical measurement. The results showed that the mass fraction of phosphorus in coating was increased with the increasing of mass concentration of sodium hypophosphite in plating bath, making the micromorphology and corrosion resistance of Pd coating better initially and then worse. The Pd coating containing 5.71% of phosphorus which was plated from the bath containing 5 g/L of sodium hypophosphite had the best surface morphology and corrosion resistance. All of the Pd coatings obtained were amorphous with excellent solderability.更多还原