Márcio R. Silva

By Guido Boidi, Philipp G. Grützmacher, Markus Varga, Márcio Rodrigues da Silva, Carsten Gachot, Daniele Dini, Francisco J. Profito and Izabel F. Machado

This work critically scrutinizes and compares the tribological performance of randomly distributed surface pores in sintered materials and precisely tailored laser textures produced by different laser surface texturing techniques. The pore distributions and dimensions were modified by changing the sintering parameters, while the topological features of the laser textures were varied by changing the laser sources and structuring parameters. Ball-on-disc tribological experiments were carried out under lubricated combined sliding-rolling conditions. Film thickness was measured in-situ through a specific interferometry technique developed for the study of rough surfaces. Furthermore, a machine learning approach based on the radial basis function method was proposed to predict the frictional behavior of contact interfaces with surface irregularities. The main results show that both sintered and laser textured materials can reduce friction compared to the untextured material under certain operating conditions. Moreover, the machine learning model was shown to predict results with satisfactory accuracy. It was also found that the performance of sintered materials could lead to similar improvements as achieved by textured surfaces, even if surface pores are randomly distributed and not precisely controlled.

Part of the book: Tribology of Machine Elements

By Suzan P. Vasconcellos, André Paganotti, Vitor G. Vital, Lidiane M. Santos Lima, Giovanna S.M. Paiva, L. Furlaneto de Lima, Enrique Moreira, Leticia O. Sousa, Guilherme G. Guerini, Vinicius T. Santos, Flavia G. Lobo, Márcio R. Silva, Diogo S. Pellosi and Ricardo A.G. Silva

In this chapter, it was introduced about the metallurgic effluents, and their potential to be converted into some feasible coproducts for industries. Some possibilities to introduce circular economy in the context of metallurgic effluents, and in the same way, some techniques to promote bioremediation using microorganisms and products from them were also described. Reported studies, as well as some perspectives to use metal-rich effluents in agriculture and soil quality improvement, were also shown. Copper effluents were kept as the main candidate for sustainable use, as a potentially interesting material for circular economy approaches.

Part of the book: Bioremediation for Global Environmental Conservation