Ultra-Fine Piercing by Ceramic Fiber Punch

微孔是传感器、过滤器、发动机喷嘴、喷墨打印机等所必需的。随着对孔尺寸的要求越来越小，对钻孔、激光穿孔、电火花加工和穿孔等微孔加工的研究也越来越多。在生产效率和成本方面，冲孔工艺更为可取，广泛应用于大批量生产中，如IC铅焰等电子零件的100 μm厚金属的冲裁。然而，由于冲模的制造和对中困难，传统方法无法实现进一步的小型化。虽然微细穿孔工具可以通过电线电火花磨削精确制造，但这仍然是一个费力和昂贵的过程。另一方面，有人提出了一种比较简单和经济的方法，用陶瓷纤维作冲孔，并通过对铝、铍铜和不锈钢箔的实验，证实了得到真正的圆孔和锐孔。然而，也发现刀具寿命太短，无法将该方法投入实际应用。在本研究中，调查了这一问题的原因，并提出了两个对策。经过连续的穿孔试验，改进后的系统对各种金属箔都是有效的。

Micro holes are necessary for sensors, filters, injection nozzle of engine, ink jet printer and so on. As the requirement of hole size becomes smaller, researches for micro hole processed by drilling, laser perforation, electro-discharge machining (EDM) and piercing have been increased. With regards to productivity and cost, piercing is preferable and widely used in mass production which includes blanking of about 100 μm thick metals for electric parts such as IC lead flame. However, further miniaturization is not expected by conventional methods because of difficulty in making punch and die and centering of them. Although micro piercing tools could be made precisely by wire electro-discharge grinding, this is still a laborious and costly process. On the other hand, one of the authors had proposed a rather simple and economic method by using ceramic fiber as a punch and confirmed that truly round and sharp-edged holes were obtained through the experiment with aluminum, beryllium copper and stainless steel foils. However, it was also found that tool life was too short to put this method into practical use. In this research, reasons for this problem were investigated and two counterplans were proposed. As the result of continuous piercing tests, improved system was effective for various metal foils.