【摘要】 采用二次离子质谱仪分析了微量元素在低压电解电容器用阳极冷轧铝箔表层的浓度分布。用扫描电子显微镜观察了冷轧箔300℃和500℃真空退火1h后的腐蚀形貌,并检测了相应的比电容值。结果表明,微量元素会不同程度地偏聚在铝箔表层,并进一步富集于表层的位错、机械划痕等缺陷附近。300℃退火1h可以促使铝箔中的微量元素向表面位错附近的富集,但不足以实现向机械划痕区域的富集。500℃退火1h不仅可以实现微量元素向机械划痕区域的富集,而且还会降低缺陷区域平衡偏聚的浓度,使铝箔表面微量元素的分布趋于均匀化。在铝箔的腐蚀过程中点蚀优先在表面缺陷与微量元素相结合的部位出现。表面均匀分布的微量元素会减小点蚀孔坑的大小,并提高点蚀孔坑的密度和腐蚀箔的比电容。更多还原

【Abstract】 The depth profile of microelements in cold rolled aluminum anode foil for low voltage electrolytic capacitor and its etching morphology after annealing at 300℃ and 500℃ for 1h were investigated based on secondary ion mass spectrometry analysis and microstructure observation under scanning electron microscope.The specific capacity of the etching foils was also measured.It showed that microelements may segregate to certain extent on the surface layer and be further enriched at foil defects such as dislocations,roll marks et al.The annealing treatment at 300℃ for 1h could prompt the enrichment of microelements at dislocations,but could not enrich the microelements along the roll marks.The annealing treatment at 500℃ for 1h could not only enrich the microelements along the roll marks,but also reduce the equilibrium segregation concentration of the microelements at the foil defects which distributed more uniformly on the surface.Etching pits were initiated preferably at the surface defects with higher microelements concentration during the etching process.The uniform distribution of microelements on the surface could reduce the size of the etching pits,increase the density of etching sites and enhance the specific capacity of etching foil.更多还原