Tribological effect of micro surface irregularities (surface porosity and texture) on lubricated sliding/rolling tests

• Grant number: 17/21151-8
• Support type: Scholarships abroad - Research Internship - Doctorate (Direct)
• Effective date (Start): April 02, 2018
• Effective date (End): April 01, 2019
• Field of knowledge: Engineering - Mechanical Engineering
• Principal researcher: Izabel Fernanda Machado
• Grantee: Guido Boidi
• Supervisor abroad: Daniele Dini
• Home Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Research place: Imperial College London, England
• Associated to the scholarship: 16/25067-9 - Study of the micro surface irregularities (texture and porosity) effect on the tribological behavior of a steel sintered by SPS, BP.DD

Abstract

This research project aims to evaluate the tribological influence of micro surface irregularities (pores and laser texture) in carbon steel during lubricated sliding/rolling tests. These materials have a potential application for manufacturing sintered gears. The sintered material will be produced by the conventional technique due to samples dimensions. Specimens' characterization will be carried out by relative density (Archimedes method), microstructural analysis (Optical Microscopy LOM, Scanning Electron Microscopy - SEM, semi-quantitative chemical analysis - EDS-SEM), X-ray diffraction and hardness measurements. Surface topography and roughness parameters will be measured using 3D optical profiling system. Sliding/rolling lubricated tests will be performed in non-compliant point contact - ball on disk. A Mini Traction Machine MTM will be used to vary the Slide-to-Roll Ratio SRR. The ball and the disk are driven by two different motors, so it allows the possibility of a great variation of SRR values. The effect of micro surface irregularities (texture and porosity) morphology, features, orientation and size will be studied in different lubrication regimes and SRR values. The counter body material is made of the chromium steel AISI 52100. A textured material will be used as a reference for benchmark tests to be compared with sintered steel in order to understand if the performance of sintered material can match those obtained with ad-hoc and more expensive solutions. This texture is applied using laser texturing and will be conducted at the IPEN or in a private company. These results will be used to validate theoretical models being produced as part of this project, whose main outcome is the development of an analytical or phenomenological model that contributes to understanding how micro-irregularities (texture and porosity) could change lubricant conditions and increase the efficiency of mechanical systems. (AU)

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BOIDI, G.; GRUETZMACHER, P. G.; KADIRIC, A.; PROFITO, F. J.; MACHADO, I. F.; GACHOT, C.; DINI, D. Fast laser surface texturing of spherical samples to improve the frictional performance of elasto-hydrodynamic lubricated contacts. FRICTION, JAN 2021. Web of Science Citations: 0.

BOIDI, GUIDO; DA SILVA, MARCIO RODRIGUES; PROFITO, FRANCISCO J.; MACHADO, IZABEL FERNANDA. Using Machine Learning Radial Basis Function (RBF) Method for Predicting Lubricated Friction on Textured and Porous Surfaces. SURFACE TOPOGRAPHY-METROLOGY AND PROPERTIES, v. 8, n. 4 DEC 2020. Web of Science Citations: 0.

BOIDI, G.; TERTULIANO, I. S.; PROFITO, F. J.; DE ROSSI, W.; MACHADO, I. F. Effect of laser surface texturing on friction behaviour in elastohydrodynamically lubricated point contacts under different sliding-rolling conditions. TRIBOLOGY INTERNATIONAL, v. 149, SEP 2020. Web of Science Citations: 5.

BOIDI, G.; TERTULIANO, I. S.; LIMA, L. G. B. S.; PROFITO, F. J.; MACHADO, I. F. Porosity Effect of Sintered Steel on the Frictional Performance of Conformal and Nonconformal Lubricated Contacts. TRIBOLOGY TRANSACTIONS, v. 62, n. 6 AUG 2019. Web of Science Citations: 0.