Torneamento de Ti6Al4V com ferramentas texturizadas por laser de femtossegundos

Abstract

The machining of the Ti-6Al-4V titanium alloy presents significant challenges due to its high specific strength, low thermal conductivity, high chemical reactivity, strong tendency toward adhesion, and accelerated cutting-tool wear. In this context, surface texturing of cutting tools has been investigated as a promising strategy for modifying the tribological conditions at the tool–chip and tool–workpiece interfaces and improving machining performance, particularly by extending tool life. Therefore, this study aimed to investigate the influence of microtextures produced on the rake face of cemented carbide tools during the turning of Ti-6Al-4V, evaluating their effects on machining forces, workpiece surface roughness, and tool life. The study was conducted in three experimental stages. In the first stage, different microtexture geometries were evaluated through an experimental design to identify the geometric parameters with the greatest influence on the machining process. At this stage, some configurations significantly improved the surface finish, reducing the average surface roughness (Ra) by up to 41.94% compared with the untextured tool, in addition to reducing machining forces by up to 8.64%. In the second stage, the geometric parameters of the selected textures were refined to optimize the microgroove geometry. The results indicated that certain configurations provided additional reductions in cutting forces, reaching a decrease of 8.02% compared with the conventional tool, as well as a 6.80% reduction in surface roughness. In the third and final stage, the optimized texture geometry was compared with an untextured tool and with textured-tool variants containing MoS₂ solid lubricant under finishing and roughing conditions. The results showed that, under finishing conditions, textured tools without lubricant reduced machining forces by 4.3%, whereas, under roughing conditions, the combination of texture and MoS₂ resulted in reductions of up to 57.9% in machining forces. Regarding surface roughness, improvements of up to 8% were observed during finishing, depending on the machining condition. Tool-life analysis indicated that textured tools without solid lubricant exhibited the best overall performance, achieving greater volumes of removed material before reaching the end-of-tool-life criterion, with average increases of 58% under finishing conditions and 24% under roughing conditions.