Salvador, Brazil
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Nunes S.G.,State University of Santa Cruz | Nunes S.G.,Federal University of Rio Grande do Sul | Da Silva L.V.,Federal University of Rio Grande do Sul | Amico S.C.,Federal University of Rio Grande do Sul | And 2 more authors.
Materials Research | Year: 2017

This work addresses the use of piassava fibers (PF) as reinforcement for recovered polypropylene (PPr) in the manufacturing of composites. The composites were molded with variable amounts of PF (10, 20 and 30 wt%), with and without maleic anhydride functionalized polypropylene (MAPP) (10 wt%) as compatibilizer. The composites were characterized using mechanical tests (flexural, tensile, impact and hardness), thermal analyses (thermogravimetric analysis and differential scanning calorimetry), along with evaluations of heat deflection temperature, melting flow index, density and morphology. Tensile and flexural strength of composites increased with PF content, but impact strength decreased, since the material became stiffer. The use of MAPP in the formulations yielded superior properties, showing good fiber/matrix interaction. In all, the use of PF as reinforcement in PPr was considered an interesting way of reducing solid waste and to reinforce plastics, being a possible alternative for the substitution of wood in WPC composites. © 2017, Universidade Federal de Sao Carlos. All rights reserved.

Machado S.L.,Federal University of Bahia | da Silva Paes Cardoso L.,SENAI CIMATEC | de Oliveira I.B.,Federal University of Bahia | de Faria Mariz D.,Petrobras | Karimpour-Fard M.,Iran University of Science and Technology
Transport in Porous Media | Year: 2016

This paper presents the results of permeability tests performed using different organic fluids and soil types in order to derive a model to predict soil permeability based on the soil water permeability values. The equation proposed by Nutting (Am Assoc Petrol Geol Bull 14:1337–1349, 1934), which uses the concept of intrinsic permeability, was extended in order to take into account the fluid and solid particle interactions. The properties of soil (plasticity index, (Formula presented.) , water permeability, (Formula presented.) and water saturation, (Formula presented.)) and fluid (density, (Formula presented.) , viscosity, (Formula presented.) , and relative dielectric constant, (Formula presented.)) were used in the model. The model results demonstrated good adherence to experimental values ((Formula presented.)). An error of about 6.4 times for the predicted soil permeability values was obtained, considering a confidence interval of 90 %. Experimental results extracted from technical literature were used to validate the model, using the same fitting constants as the experimental dataset of the authors. The model was able to capture the variation in the experimental results, although more than 10 % of the experimental results are located outside the confidence interval. © 2016, Springer Science+Business Media Dordrecht.

Lukacs L.,Ford Motor Company | Dassanayake M.,Ford Motor Company | Magalhaes R.,SENAI CIMATEC | Fontes C.,Federal University of Bahia | And 2 more authors.
International Journal of Automotive Technology | Year: 2011

The vehicular illumination system has undergone considerable technological advances in recent decades such as the use of a Light Emitting Diode (LED) Adaptive Front-lighting System (AFS), which represents an industry breakthrough in lighting technology and is rapidly becoming one of the most important innovative technologies around the world in the lighting community. This paper presents AFS control alternatives using fuzzy logic (types 1 and 2) to determine its operating parameters taking into consideration the road conditions in the state of São Paulo (Brazil). Fuzzy logic is a well-known extension of the conventional (Boolean) logic that enables the treatment of uncertainty present in the information through the definition of intermediary membership values between the "completely true" and the "completely false". This technique or modeling strategy is particularly important when a multi-parameter decision must be taken or the decisions are based on the human knowledge. The results show the potential of the methodology proposed and its suitability for light control providing safer nighttime driving. © 2011 The Korean Society of Automotive Engineers and Springer-Verlag Berlin Heidelberg.

Tanajura A.P.M.,SENAI CIMATEC | Tanajura A.P.M.,Federal University of Bahia | Oliveira V.L.C.,Federal University of Bahia | Lepikson H.,SENAI CIMATEC | Lepikson H.,Federal University of Bahia
Lecture Notes in Electrical Engineering | Year: 2015

Multi-agent systems have been successfully used to represent distributed manufacturing systems. Each part or characteristic of the system can be represented by an agent which acts independently and in a cooperative way. A better integrated operation can emerge as the result of each agent following its own rules and communicating with the others. Better decisions from a holistic viewpoint can be achieved when manufacturing asset management is supported by a multi-agent approach. A model to manage distributed manufacturing is proposed and applied to on-shore oil fields. The distributed characteristics of oil field units, such as wells, collecting stations, compressing stations and supplies mean that they have to cooperate to reach production targets. The integrated management model carries out a cost analysis and helps to identify unprofitable assets and to support decision making processes. Agents help to reduce the load of information for the operator, giving more time to focus on situations that require greater attention. Example applications are presented in which the proposed multi-agent model, its ontology and rules, could help oil field surveillance and support decision-making process. © Springer-Verlag Berlin Heidelberg 2015.

Andrade L.P.C.D.S.,SENAI CIMATEC | Silva R.C.D.,Brazilian Technological Institute of Aeronautics | Mascarenhas L.A.B.,SENAI CIMATEC | Gomes J.D.O.,Brazilian Technological Institute of Aeronautics | Marinho F.D.S.,SENAI CIMATEC
Procedia CIRP | Year: 2016

A considerable bottleneck in Brazil is the lack of technology centers aimed at industrial R&D. On one side, universities conduct basic research that is usually does not go beyond bench testing. On the other side, companies have their structure focused on large-scale production. Pilot plants, which are fundamental environments for the innovation process, are rarely found within Brazilian companies. This paper proposes a model for an innovative infrastructure, focused on meeting industrial demands that require special conditions of operation and control. Its scope is limited to supporting innovation mainly in the pre-competitive stage of product and process development. To this effect, the proposed model consists of a technology service center, embedded in an industrial environment, which focuses on production scale-up, large scale testing, manufacturing/assembly of pilot plants, and development of real size prototypes. Through these activities, this center is expected to give full support to technological development and to industrial innovation processes. In order to validate this proposal, an environment was modeled for the development of renewable energy solutions, which encompasses scale-up, testing and certification. © 2016 The Authors.

Andrade L.P.C.D.S.,SENAI CIMATEC | Ferreira C.V.,Federal University of Santa Catarina | Silva R.C.D.,Brazilian Technological Institute of Aeronautics | Gomes J.D.O.,Brazilian Technological Institute of Aeronautics
Procedia CIRP | Year: 2016

Industrial competitiveness has required from companies elevated quality standards, cost reduction and a high capacity of delivery. Within this scenario, an important industrial segment has a fundamental role: the tool and die industry. Tools and dies are resources that are fit to a specific task and are either produced as a single-unit batch or intermittently according to demand. Generally, this industrial segment has demonstrated low competitiveness, which in turn affects the performance of other production chains that rely on it. This is the case of the plastic transformation and metalworking industry, especially when forged and stamped parts are considered. This low competitiveness is a consequence of the deficient corporate structure found in these companies, which results in lack of compliance to quality standards, high costs and long delivery times. Besides the support given to current tool-and-die making clusters, a decentralization structuring project of this industry to other regions of Brazil is necessary. This need is illustrated by new automotive and other consumer goods production plants that have recently started operating in the northeast and central regions of Brazil. In order to contribute to this issue, this article proposes a strategic management model for the incubation process of industrial companies that comply with competitiveness standards required by current market demands. Besides the usual difficulties related to incubation and the creation of any enterprise, the tooling industry faces an additional obstacle related to investment in assets (buildings, machinery, and software). Therefore, a nucleation process based on an existing structure that will be shared by several companies is proposed (IDS-Industrial Development Structure). This structure shall be preferably established on an ICT (Brazilian denomination for Science and Technology Institutes) that shall contribute with professional training (tool and die making) and specialized services (e.g. metrology and tool tryouts). © 2016 The Authors.

Paggi R.A.,Federal University of Santa Catarina | Beal V.E.,SENAI CIMATEC | Salmoria G.V.,Federal University of Santa Catarina
International Journal of Advanced Manufacturing Technology | Year: 2013

Nanocomposites produced through the addition of carbon nanotubes to a polymeric matrix can improve the material properties. The mobility of the polymer chains is usually affected, and this is also related to the properties. Parts produced with the free-form fabrication process using the selective laser sintering (SLS) technique can be used in different high-performance applications as they do not require expensive tools for their manufacture. A specific field of interest is the aerospace industry which is characterized by a low production volume and the need for materials with a high performance to weight ratio. In this study, the free-form fabrication by SLS of parts made from nanocomposites comprised of polyamide 12 and multiwalled carbon nanotubes (MWCNTs) was investigated. Specimens were manufactured by SLS to identify the appropriate processing parameters to achieve high mechanical properties for aerospace applications. Laser energy density was adjusted to improve the material density, flexural modulus, and stress at 10 % elongation. Design of experiments was used to identify and quantify the effects of various factors on the mechanical properties. The results obtained showed that there was a limit to the amount of MWCNTs which could be mixed with the polyamide powder to improve the mechanical properties since a higher content affected the laser sintering process. © 2012 Springer-Verlag London Limited.

Yurgel C.C.,Senai Cimatec | Lora F.A.,Senai Cimatec | de Oliveira C.A.S.,Federal University of Santa Catarina | Schaeffer L.,Federal University of Rio Grande do Sul
International Journal of Material Forming | Year: 2015

This work has the objective of evaluating the effect of electromagnetic stirring (EMS) used in continuous ingot (CI) in the mechanical and metallurgical properties of hot forged flanges of AISI 1025 steel. Three conditions of raw material were supplied and compared before the forging process: one from CI using EMS; the other, prevenient from CI without EMS, and the last, with CI without EMS, and, subsequently, submitted to hot rolling process. Billets were extracted from these raw materials to manufacture connection flanges through hot forging. To evaluate the mechanical properties of the forged pieces, tension, hardness and impact tests were done, and the microstructure was observed by optical microscopy. Macrographs and penetrating liquid non-destructive testing were also done. The results of the above-mentioned tests showed proximate mechanical and metallurgical properties approved by the reference norm (ASTM A105) of the flanges manufactured with the raw materials obtained by CI with EMS and hot rolling. © 2013, Springer-Verlag France.

Mascarenhas L.A.B.,SENAI CIMATEC | Gomes J.D.O.,ITA CCM | Beal V.E.,SENAI CIMATEC | Portela A.T.,SENAI CIMATEC | And 2 more authors.
Wear | Year: 2015

A current trend in the automotive industry is to reduce the engine size while increasing power. The valve and valve seat perform the functions of ensuring the entry of air and combustible material, the output of combustion gases and sealing during the compression and combustion processes. As a result, the pair valve and seat are the most critical components in high-efficiency engines. To ensure the robustness of their operation while providing clean combustion and low emissions, the use of the correct materials is required. The high temperatures of the exhaust gases, the velocities of the valves and the high operating pressures are several of the parameters that cause wear on the valve seats and valves. The materials used to create the valve must be characterized by good workability, high wear resistance, good mechanical strength and good fatigue and corrosion resistance at high temperatures. However, the tests applied to develop new materials are limited to lower temperatures than those expected in the next generation of combustion engines. In this study, the development of a new valve seat and valve test machine for high temperatures is presented. A comparison of the currently available designs of apparatuses for this purpose is also presented with the new proposed design. The results of testing the valve seats and valves using this new design are presented and evaluated along with the results of the standard test machines. © 2015 Elsevier B.V.

Breda Mascarenhas L.A.,SENAI CIMATEC | De Oliveira Gomes J.,ITA CCM | Portela A.T.,SENAI CIMATEC | Ferreira C.V.,Federal University of Santa Catarina
Procedia CIRP | Year: 2015

The trend in the automotive industry is to reduce the size of engines while increasing power. The concept of leveraging considers not only the efficiency of manufacturing a product but all consumption of energy or other natural resources during the life cycle of the product. In this process, one of the bottlenecks to more efficient engines is the exhaust valve. The valve and valve seat together perform the function of ensuring the entry of air and combustible material, the output of combustion gases and the sealing function during the compression and combustion processes. The valve is the most demanding component in high efficiency engines. To ensure the rigor of operation while providing clean burning and low emissions, the application of special materials is necessary. The extremely high temperatures of the exhaust gases, the velocities of valves and the high operating pressure are only some of the parameters that cause wear on valves. The materials used in valve production must be characterized by good workability, low wear, good mechanical strength and good fatigue and corrosion resistance at high temperatures. In this context, the CCM / ITA and SENAI CIMATEC jointly developed a workbench to simulate the durability of valves and valve seats, analyze their wear resistance and evaluate their behavior with varying parameters. This paper shows the workbench development process and a new testing method that considers the high engine operation temperatures and focuses on reducing the new material development life cycle and the emissions during the product usage life time. © 2015 The Authors. Published by Elsevier B.V.

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