Desgaste da ferramenta e integridade superficial no microfresamento da liga de Titânio Ti-6al-4v

Abstract

Among the manufacturing processes, micro-machining is one of the most precise, allowing the manufacture of extremely small and useful parts for the current market, especially for those sectors that require small and low weight artifacts, as well as very low failure rates. Even though it still needs improvement, micro-machining is capable of processing several varieties of metals and their alloys, composites, polymers and ceramics. Also, through this process, it is possible to obtain exact dimensions and narrow tolerances. Thus, this work has as main objective to evaluate the influence of the feed rate on tool life and surface integrity when micro-milling Ti-6Al-4V titanium alloy using 254 μm uncoated carbide tools. The feed rate was the only parameter evaluated, the others were kept constant for all the experiments. The surface integrity was evaluated by the formation of burrs. The height of the burrs formed during the micro-milling was measured. In addition, an analysis of the machined surface was carried out in the scanning electron microscope (SEM). The wear of the tools was evaluated through SEM images, and a qualitative analysis was carried out, comparing the tools before and after the machining, as well as comparing the tools for all the cutting conditions used. It has been observed that the burrs are smaller when the feed rate increases, but the wear of the tool increases, affecting useful life. In addition, it was noticed that the burrs formed at the down-milling side were shorter than the burr at the up-milling side of the slots.