Ti6Al4V turning with femtosecond laser textured tools

Abstract

Machining the Ti6Al4V alloy is challenging due to its mechanical properties, such as high strength, low thermal conductivity, and high reactivity against all currently available tool materials. To address these challenges and enhance process efficiency, strategies such as tool texturing have emerged as promising alternatives. This research investigated the effect of groove-type textures produced by femtosecond laser on the rake face of carbide tools during the turning of the Ti6Al4V (Grade 5) alloy, using flood application of cutting fluid. Various texture configurations were studied, with a particular focus on texture orientation, dimensions, and distance from the cutting edge, as well as feed rate as a key cutting parameter. The objective was to understand the impact of these textures on machining performance and optimize the process, primarily by analyzing cutting forces and workpiece roughness as response parameters. Initially, the texture characteristics were defined based on average values found in the literature for turning Grade 5 titanium, ensuring a well-founded approach to selecting the experimental conditions. To optimize the process, a CCD (Central Composite Design) and RSM (Response Surface Methodology) were used, allowing statistically organized experiments to be conducted. This method enabled the development of predictive models that help understand the behavior of textured tools under different machining conditions. The results showed that the effectiveness of texturing is not uniform across all feed rate ranges investigated. In certain conditions, textures reduced cutting forces and improved the quality of the machined surface, while in others they did not provide significant benefits, although the cutting forces were more sensitive to texture variations than workpiece surface roughness. Overall, the results of this study demonstrate that femtosecond laser texturing of tools is a promising strategy for improving the turning of the Ti6Al4V alloy.