Avaliação da qualidade superficial no torneamento interno sob diferentes condições de construção e amortecimento de ferramentas

Abstract

The pursuit of higher surface quality and greater stability in machining processes has driven the development of tools with different design characteristics and vibration-damping systems. In this context, the present study aimed to evaluate the influence of tool design characteristics and damping capacity on the surface finish obtained in internal turning operations. For this purpose, three different tools were analyzed: a standard tool, an induction-hardened tool body, and a Silent Tools™ anti-vibration tool. The experiments were carried out on a Mazak Integrex 300-III machining center using SAE 1080 steel as the reference material, while maintaining constant cutting parameters. Surface quality was evaluated through the measurement of roughness parameters Ra and Rz, as well as waviness parameters Wa and Wz, using a Mahr MarSurf GD 25 roughness tester. Each sample was measured three times, and the average value was considered in order to increase the reliability of the results. The results showed that the standard tool presented the highest roughness and waviness values, indicating greater susceptibility to vibrations and dynamic instability during the machining process. The induction-hardened tool exhibited the best overall performance, with low levels of roughness and waviness, demonstrating greater system stability. The Silent Tools™ tool presented the lowest average roughness values, indicating excellent surface finish at the microscale; however, it showed intermediate waviness values, suggesting limitations in controlling low-frequency vibrations. The analysis of the results demonstrated that roughness alone is not sufficient to fully characterize the quality of a machined surface, making the combined evaluation of waviness parameters necessary. Therefore, it can be concluded that tool performance is directly related to its ability to control vibrations, with the balance between structural rigidity and damping being the determining factor for achieving better results in internal turning operations. [resumo fornecido pelo autor]