The review describes recent progress on understanding and quantification of the various phenomena that take place during plasma electrolytic oxidation, which is in increasing industrial use for production of protective coatings and other surface treatment purposes. A general overview of the process and some information about usage of these coatings are provided in the first part of the review. The focus is then on the dielectric breakdown that repeatedly occurs over the surface of the work-piece. These discharges are central to the process, since it is largely via the associated plasmas that oxidation of the substrate takes place and the coating is created. The details are complex, since the discharge characteristics are affected by a number of processing variables. The inter-relationships between electrical conditions, electrolyte composition, coating microstructure and rates of growth, which are linked via the characteristics of the discharges, have become clearer over recent years and these improvements in understanding are summarised here. There is considerable scope for more effective process control, with specific objectives in terms of coating performance and energy efficiency, and an attempt is made to identify key points that are likely to assist this.

中文翻译：

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各种金属等离子电解氧化过程中放电特性的最新研究综述

这篇综述描述了在了解和量化等离子电解氧化过程中发生的各种现象方面的最新进展，这在工业上越来越多地用于生产保护性涂层和其他表面处理目的。在审查的第一部分中提供了该过程的一般概述以及有关这些涂层的用法的一些信息。然后，重点是在工件表面上反复发生的介电击穿。这些放电是该过程的中心，因为很大程度上是通过相关的等离子体发生了基材的氧化并形成了涂层。由于放电特性受许多处理变量的影响，因此细节很复杂。电气条件，电解质成分，通过放电特性相互联系的涂层微观结构和生长速率在最近几年变得更加清晰，在此总结了对理解的这些改进。对于更有效的过程控制，还有相当大的余地，对于涂层性能和能效方面都有特定的目标，并且试图确定可能有助于这一点的关键点。