Análise da influência da contaminação do lubrificante por biodiesel em um equipamento Pin-on-disk

Pós-graduação em Engenharia Mecânica - FEIS

A produção enxuta em um sistema de fabricação contínuo: aplicação da simulação discreta estocástica na indústria de condutores elétricos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Aspectos ergonômicos e de segurança no uso dos autômatos: estudo de caso nas regiões sul fluminense e vale do Paraíba

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Electrochemical Determination of Organic Compounds in Automotive Fuels

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

MICROSTRUCTURAL CHARACTERIZATION OF DUAL AND MULTIPHASE STEELS APPLIED TO AUTOMOTIVE INDUSTRY

TRIP (Transformation Induced Plasticity) and DP (Dual-Phase) steels are written in a new series of steels which present excellent mechanical properties. As for microstructure aspect, TRIP steels consist on a ferrite matrix with a second phase dispersion of other constituents, such as bainite, martensite and retained austenite, while dual-phase steels consist on martensite dispersion in a ferrite matrix. In order to identify the different microconstituents present in these materials, microstructure characterization techniques by optical microscopy (using different etchants: LePera, Heat-Tinting and Nital) and scanning electron microscopy were carried out. This being so, microstructures were correlated with mechanical properties of materials, determined by means of tensile tests. It is concluded that steels assisted by TRIP effect have a strength and elongation relation higher than the dual-phase one. With microstructure characterization, it was observed phases present in these materials microstructure.

MICROSTRUCTURAL CHARACTERIZATION OF CP STEEL USED IN AUTOMOTIVE INDUSTRY

This study aims to characterize the microstructure of the complex phase steel (CP). Using the conventional and colored metallographic analysis with 3% Nital etchant, sodium metabisulfite 10% and LePera. Techniques were applied in this work of optical microscopy, using, besides the lighting in bright field, dark field illumination of the reverse contrast in bright field illumination, the method of polarized light, which generates colorful contrast, providing a complementary identification phases present in the microstructure, and the system by differential interference contrast (DIC). The results obtained by metallography CP indicates that the steel has a microstructure composed of ferrite, retained austenite, bainite and martensite and precipitates arranged in a refined and complex morphology. Besides bright field illumination others' optical microscopy's techniques such as dark field illumination were applied.

Avaliação da auto-suficiência energética em reatores anaeróbios aplicados ao tratamento de resíduos da indústria de produção do etanol

Ethanol, the main automotive biofuel, has its production based on the fermentation of sugars found in biological materials and on the distillation of the alcoholic media formed during the fermentative process. Stillage is the main residue from ethanol production, containing a high organic loading in addition to acidic and corrosive characteristics. Considering the available technologies to treat stillage, we highlight anaerobic digestion, which allows the reduction of the impacts associated to pollutants loading of this effluent and the generation of energy from the methane gas produced in the process. Based on the high treatment efficiency usually associated to the anaerobic process, this work aimed to assess whether anaerobic systems applied to the treatment of stillage are energetically self-sufficient. First we evaluated the energy recovery capacity in an anaerobic reactor applied to the treatment of stillage resulting from corn-to-ethanol processing. The results indicated the great influence that a correct selection of electrical equipment and their respective operating periods have on the net energy balance of the anaerobic treatment. The high energy consumption of the heater would not allow the system to achieve a positive net energy balance – the maximum energy recovery would reach only 0.68% of the consumption. However, the replacement of the mixture equipment would result in energy gains ranging from 8.5 to 967.9% of the consumption. In this work we also assessed the efficiency of methane yields for a few studies and the correlation between some parameters of the anaerobic process. With respect to the methane yield, we noted that mesophilic systems tend to be more advantageous than the thermophilic ones (efficiency of 76.45 ± 22.51% vs. 69.40 ± 30.36%). Considering the study... (Complete abstract click electronic access below)

Recycling scrap automotive heat shield insulation material

Automotive heat shields are usually composed of two metal sheets enclosing an insulating material with a paper-like texture that contains refractory ceramic particles. This article discusses the results achieved by recycling the scrap automotive insulation that is discarded in landfills, using the same concept as paper recycling. For comparison with the original product, tests of thickness, bulk density, weight loss on ignition, tensile strength, compressibility, and recovery were performed on recycled materials produced in a so-called "manual" process (involving little automation and performed in adapted facilities) without pressing, and pressed once, twice, and four times. Materials recycled in a so-called "industrial" process (in a paper recycling plant) without pressing, and pressed once were also tested. The recycled materials can be considered approved with respect to the main requirement, thermal insulation, since they dissipated the under-hood temperature by more than 300 A degrees C (like the original product). Like the heat insulation tests, the thermogravimetric analysis suggested that the recycled materials showed higher stability than the original product. Thermogravimetric, microscopy, and energy dispersive spectroscopy analyses indicated that the structural and compositional characteristics of the original product were preserved after recycling.

Analysis of the influence of baffles and shields on the cooling of a digital transmission equipment

In this work design criteria for cooling of electronic systems used in a digital transmission equipment are considered. An experimental study using a simulated electronic equipment in which vertically oriented circuit boards are aligned to form vertical channels is carried out. Resistors are used to simulate actual components. The temperature of several components in the printed circuit boards are measured and the influence of the baffles and shields on the cooling effect are discussed. It was observed that the use of the baffles reduce the temperature levels and, the use of shields, although protecting the components from magnetic effects, cause an increase in the temperature levels.

Open innovation and user s involvement in new product development: a case study in the automotive sector

Innovation is an essential factor for obtaining competitive advantages. The search for external knowledge sources for product creation, which can contribute to the innovation process, has become a constant among companies, and users play an important role in this search. In this study, we aimed to analyze user’s involvement in the product development process based on open innovation concepts. We used the unique case study research method. This study was carried out in an automotive company that has developed a project of a concept car involving user’s through the Web 2.0. With such scope, the research demonstrates that users can contribute not only with generation of ideas but also with the innovation process itself.