PG-EAM - Graduate Program in Aeronautical and Mechanical Engineering
PT EN
Master's Dissertation 2023

The interaction between grinding and isotropic superfinishing in the gear manufacturing chain

Author

Gilberto Martins de Oliveira Gomes

Advisor

Concentration Area

Materiais e Processos de Fabricação

Defense Date

08/02/2023

Thesis Number

79013

Abstract

The electrification of mobility is seen as a way to minimize greenhouse gas emissions since transportation based on an internal combustion engine is responsible for about 15% of the global carbon dioxide emission. Electromobility is accompanied by tighter surface quality requirements of the transmission gears. Due to the possibility of providing a highly smooth surface and a homogeneous loading distribution, the isotropic superfinishing process has been taken as a possible application in electromobility gears. On the other hand, the interaction of the isotropic superfinishing with its previous manufacturing stages, and their corresponding characteristics, is not explored by the state-of-the-art. The objective of this study is to identify the influence of the grinding process on the superfinished surface. Thus, the variation of the grinding parameters will be explored to induce different surface integrity states that are further processed in isotropic superfinishing. As a result, the study allowed us to verify the effect of isotropic superfinishing on the topography. Thus, the process is efficient in reducing roughness, reaching a reduction rate of 53% to 61% in the value of the average roughness. The study also highlights the changes in surface integrity. It was also possible to verify the effect of chain variation in isotropic superfinishing processing. To this end, different surface integrity states were generated from different grinding conditions that were subsequently subjected to the isotropic superfinishing process, which in turn conserved heterogeneity and residual stress intensity. This evaluation allowed us to verify that the grinding process is influential in the superfinishing process, where different residual stress states were generated at the end of the manufacturing chain. This evaluation is directly related to the concept of Design for Residual Stress, where the processes prior to superfinishing had an influence on the state of surface integrity.

Keywords

Engrenagens Tensão residual Motores elétricos Tratamento de superfícies Integridade Engenharia mecânica