Estudo do microfresamento do aço ferramenta AISI H13 com ferramentas de diferentes geometrias

Abstract

The advancement of technologies has driven the need to manufacture components with increasingly smaller dimensions. To meet this demand, micromilling has been widely used. This process is applied to various materials, including tool steels like AISI H13 tool steel, which is often used in the production of molds and dies for high-temperature operations. In this context, the micromilling of H13 steel has been the subject of numerous studies, focusing on the analysis of phenomena associated with the process and the evaluation of its quality. However, there is a research gap about the influence of the tools used in micromilling, as the geometry of micro end mills directly affects the final quality of the parts and production costs. Therefore, this study aims to evaluate the performance of different tools in the micromilling of ABNT H13 steel. Three straight-end micro end mills with a diameter of 400 μm, featuring different geometries and coatings, were used. The experiments were conducted on a high-precision CNC micromilling machine, using cutting fluid under the minimum quantity lubrication (MQL) regime, and keeping constant cutting parameters initially. Tests were also performed with different cutting parameters for each micro end mill, according to the manufacturer's recommendations. The wear of the micro end mills, the roughness of the machined surface, and burr formation were evaluated. It was found that adhesion was the primary wear mechanism. Cutting parameters and tool geometry did not influence wear. However, geometries affected the roughness results, with the lowest Ra value being 0.0607 ± 0.0027 µm. Geometry also influenced burr formation concerning the micro-milled distance, along with cutting parameters affecting burr height. The smallest burrs were obtained with the lowest material removal rates. The micro-end mill with the best performance was the VF2XLD0040N010.