Applying punching without die to micro-hole array processing

Abstract

Aluminum alloy (Al6061) sheet micro-hole processing is extensively used in smartphones, tablet PC, and smart wearable devices. The micro-hole processing is commonly performed using laser, micro drilling, micropunching, micro discharge, and chemical etching technologies. Micro-punching technology is characterized by precision and rapid processing, but the precision positioning of the punch head and lower die is one of the major difficulties in micro-hole punching, especially in manufacturing array micro-holes. This study used punching without die technology. This technology uses an array punch head to punch the lower die holes on the base, then performs array micro-hole punching. The experimental results show that a micro-hole array with 37 micro-holes were successfully manufactured and can be reproduced many times. Tapered array micro-holes with a high aspect ratio can be manufactured using this punching without die technology; the micro-hole depth can be 260 μm, the inlet diameter is 116 μm, and the outlet diameter is 25 μm. This study has successfully developed the feasibility of array micro-hole punching technology.