(1. 中南大學 材料科學與工程學院, 長沙 410083;
2. 中南大學 有色金屬材料科學與工程教育部重點實驗室, 長沙 410083)
摘 要: 通過極化曲線測試鋁箔的腐蝕電位，結(jié)合光學顯微鏡和掃描電鏡等觀察鋁箔腐蝕發(fā)孔后的表面形貌，探討最終退火工藝和酸堿預處理對高壓電子鋁箔腐蝕發(fā)孔性能的影響規(guī)律。結(jié)果表明：鋁箔在經(jīng)不同溫度 (470~560 ℃)和不同時間(0.5 h~4 h)的最終退火處理時，當鋁箔經(jīng)500 ℃, 1 h退火后，各種有利于發(fā)孔的元素擴散到鋁箔表層、富集并且均勻分布，此時的發(fā)孔效果最好，繼續(xù)升高退火溫度和延長退火時間反而會使發(fā)孔變得不均勻；發(fā)孔前堿處理能適當減少鋁箔表面的氧化層，酸處理則將Cl−引入鋁箔表面，酸+堿清洗使鋁箔的腐蝕電位降低，促進鋁箔的腐蝕發(fā)孔，腐蝕后的發(fā)孔面積和密度比未經(jīng)預處理的大，發(fā)孔更均勻。
關鍵字: 高壓電子鋁箔；最終退火；預處理；腐蝕；發(fā)孔
pitting ability of aluminum foils
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Non-ferrous Metal Materials Science and Engineering, Ministry of Education,
Central South University, Changsha 410083, China）
Abstract:The influence of the final-annealing parameters and pretreatment before etching on the etching ability of the high voltage aluminum foils was investigated. The distribution of pits and the morphological features after etching were observed by metallographic microscopy and scanning electron microscopy. The galvano-chemistry performance of foils was analyzed by using polarization curve. The results show that when the foils are annealed at various temperatures (470−560 ℃) for different annealing times (0.5−4 h), the best annealing technology is at 500 ℃ for 1 h, which will increase the concentration as well as the distribution homogeneity of the trace elements in the surface layer; it will get bad result if the annealing temperature or the time is increased. The sodium hydroxide pretreatment before pitting can remove the oxide film of the foils, and the hydrochloric acid pretreatment makes Cl− ion enter into the surface of foils. NaOH+HCl pretreatment reduces the corrosion potential and promotes the pitting of the aluminum foils; the area and density of pit etching on the aluminum surface increase after pretreatment, and the uniformity of pitting also increases significantly.
Key words: high voltage aluminum foil; final-annealing; pretreatment; corrosion pitting
