Abstract
One of the authors developed a new micro piercing process by combining press indenting and chemical etching. By using conical and V-shaped indenters, circular and rectangular holes having tens of micrometers in size were successfully produced for 0.1mm thick copper alloy sheets, respectively. In this paper, multiple holes were pierced by this method and the influential factors on the accuracy of holes were investigated. The hole was distorted when the indenting pitch was below a specific threshold. The threshold pitch for rectangular holes was considerably larger than that for circular holes, which was explained by metal flow during indenting. As far as an adjacent hole was not distorted by subsequent indenting, dimensional accuracy of holes was affected by the tip angle of indenters, but little affected by the shape of holes.
