Ultrahigh-pressure etched foil and etching method thereof

The invention belongs to the technical field of electrode materials for capacitors, and particularly provides ultrahigh-pressure etched foil and an etching method thereof. The etching method comprisesthe following steps: pretreatment, first-stage direct current (DC) pitting etching, second-stage DC pitting etching, first middle treatment, third-stage DC reaming etching, fourth-stage DC reaming etching, second middle treatment and after-treatment, wherein three-section combined attenuation current waveforms are adopted during the first-stage DC pitting etching and the second-stage DC pitting etching. The etched foil obtained by the etching process can be applicable to ultrahigh pressure requirements of 850 V or above, and has large pit diameters, good pit consistency and higher electrostatic capacity and bending strength. 本发明属于电容器用电极材料技术领域，具体提供一种超高压腐蚀箔及其腐蚀方法。所述腐蚀方法包括：前处理；一级直流发孔腐蚀；二级直流发孔腐蚀；第一次中处理；三级直流扩孔腐蚀；四级直流扩孔腐蚀；第二次中处理和后处理；所述一级直流发孔腐蚀和二级直流发孔腐蚀均采用三段组合衰减电流波形。由该腐蚀工艺制备得到的腐蚀箔能够适用于850V以上的超高压需求，孔径大、孔的一致性好，静电容量和折弯强度均较