Investigation and Testing of the Performance and Durability of Ultra Small Diameter Micro-machining Tools.

The world of micro-tools and micro-machining is still being explored, and new manufacturing processes and tools are being developed by researchers and industry leaders alike. Many of the performance metrics for ultra-small machining tools (like end mills) are still underdefined or are currently being determined. The objective of this investigation was to determine the performance and durability of the 15 micron (um) diameter micro tool manufactured by the company Performance Micro Tool (PMT). The performance of the tool was measured by the surface roughness that resulted from the micro end mill's tool path. The durability of the tool was measured by the overall linear distance cut by the end mill before complete tool failure. In total, two micro-tools were tested, and the performance and durability results were surprising and significant. The tools surpassed the initial expectations of immediate failure upon contact with the base model. The expectation of failure stemmed from the less than ideal testing conditions for the tools -- a milling machine not capable of ideal cutting parameters and imperfections in the base model manufacturing. In terms of durability, both tools survived the entire defined tool path; over 5,000 times the tool diameter, a comparable metric for industry macro tools. The performance of the end mills was spectacular, both toolpaths had average surface roughness values below 0.05um, which is lower than the industry standard for some of the highest cut quality. Ultimately, the consistent results from both tools encourages a deeper investigation into these micro-tools. The fact that both tools exceeded expectations means that an investigation of many more tools is worth the financial and time investment. A further investigation of a large number of micro-tools could yield a standardized metric for performance and durability for the 15um tools.