Electrochemical machining is a controlled metal shaping process based on anodic dissolution performed by the electrode reactions. When pulse signals, in the micro-second or less range, are combined with a small inter-electrode gap, the process is referred to as Micro-Electro-Chemical machining or μECM. The application of using nano-second/micro second pulses for μECM for certain passivation metals can be very limited by the formation of an oxide layer that prohibits the penetration of ultra-short pulse durations due to the capacitive effect of the oxide layer. This paper will present findings from the development of a μECM numerical model that incorporates an advanced hybrid time stepping approach for representing nano-second pulse interactions with the physical phenomena of the electrolytic environment associated with μECM, thereby enabling the characterisation of the capacitive model of the formed oxide barrier layer. Experimental work was conducted using nano and micro-second pulses on the machining of 18CrNi8 and copper using NaNO3 electrolyte. The μECM simulation model contributed to quantifying the lack of faradic machining of 18CrNi8 that was experimentally observed. A particular solution, believed to be effective in breaking through the oxide film, is to directly pre-polarize the layer by super imposing a DC signal prior to the ultra-short pulses, such that its capacity has been already loaded when the short pulse signal is applied. However, too long of DC signal application time can lead to machining damage. Through the development of an ultra-short pulse simulation model, this work has established, that we can numerically determine an optimal DC signal duration necessary to load the oxide layer just enough for facilitating anodic dissolution during physical μECM process, thus minimising machining damage.

电化学加工是基于电极反应进行的阳极溶解的可控金属成型工艺。当微秒或更短范围内的脉冲信号与较小的电极间间隙结合在一起时，该过程称为微电化学加工或μECM。对于某些钝化金属，对μECM使用纳秒/微秒脉冲的应用可能会由于形成氧化物层而受到很大限制，该氧化物层会由于氧化物层的电容效应而阻止超短脉冲持续时间的穿透。本文将介绍μECM数值模型开发的发现，该模型结合了先进的混合时间步进方法，用于表示纳秒级脉冲相互作用以及与μECM相关的电解环境的物理现象，从而能够表征所形成的氧化物阻挡层的电容模型。使用纳秒和微秒脉冲对使用NaNO3电解质加工18CrNi8和铜进行了实验工作。μECM仿真模型有助于量化通过实验观察到的18CrNi8法拉第加工的缺乏。一种被认为对穿透氧化膜有效的特定解决方案是，通过在超短脉冲之前叠加一个DC信号来直接对层进行预极化，这样当短脉冲信号时其容量已经被加载被申请;被应用。但是，直流信号施加时间过长会导致加工损坏。通过开发超短脉冲仿真模型，这项工作已经建立，