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建立了一个估算在盐酸溶液中交流电解腐蚀铝箔时阴极半周铝表面液层酸度变化和预测腐蚀膜沉积的数学模型.分析结果表明 :电极表面液层酸度仅取决于盐酸本体浓度 (C0 )、外加阴极电流密度 (iappl)和交流电频率 (f) ,如果腐蚀条件满足 C0iappl 587f(f+ 1 0 .4 ) 2 ,则Al3+就可能沉淀形成腐蚀产物膜.“,”An important factor in ac etching of aluminum foil in hydrochloric acid solution is alkalization of the electrolyte near the cathode and precipitation of Al 3+ as etch film depositing on aluminum, which influence in large extent the morphology of etched surface. The mass transport process of hydrogen evolution on aluminum during the negative half-cycle of ac etching of aluminum in HCl solutions has been analyzed. An equation was derived to estimate the surface hydrogen ion concentration as a function of the bulk HCl concentration, current density and frequency of the applied alternating current on the basis of diffusion equation in which diffusion and electrical migration of H + in the electrolyte, as well as the variations of actual hydrogen reduction current density with the surface morphology of aluminum were considered. The analysis showed that the formation of etch film occurs if the actual ratio of concentration of hydrochloric acid to the applied cathodic current density is lower than or equal to the corresponding critical ratio calculated by the inequality C 0i appl 587 f(f+10.4) 2 , where C 0 is the bulk HCl concentration in mol/L, i appl is the average value of current density in A/cm 2, and f is the frequency of alternating current in Hz. The results published in literature can be interpreted satisfactorily by using the approximate formula. Thus, the etch conditions under which etch film is to be expected could be predicted on the basis of the present results.