Navegando por Autor "FUJIYAMA, Roberto Tetsuo"

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Advantages of applying composite material to replace metal alloys in aviation
(INSTITUTO DE TECNOLOGIA, 2015) BARROS, Marcelo André Santiago; FUJIYAMA, Roberto Tetsuo; LEITE, Jandecy Cabral; MAGALHÃES, Edilson Marques
Composite materials were used by early agricultural societies and their adoption has been driven by military technological needs. High fuel costs and strict environmental regulations have increased the demand for this technology in the civil sector. This article presents the application advantages of composites in aircraft structures, especially regarding weight reduction, lower operational costs, and environmental, social, and economic impacts. The research includes literature review, experimental studies, and comparisons with traditional metal alloys.
Análise da qualidade da soldagem do componente conector HDMI Mother Board Laptop
(INSTITUTO DE TECNOLOGIA, 2015) VIEIRA, Antônio da Silva; COSTA, Robson Marques; FONSECA, Cristiano Mourão; FREITAS, Carlos Alberto de Oliveira; FUJIYAMA, Roberto Tetsuo; MAGALHÃES, Edilson Marques
This paper assessed the quality of HDMI connector component welding in laptop printed circuit boards (PCBs) based on IPC-A-610D standards. The study applied the PDCA method to identify and resolve issues related to insufficient solder barrel filling. Through X-ray analysis and metallographic tests, it was demonstrated that the automated reflow soldering process (SMT) meets normative requirements, effectively replacing the manual process.
Análise de Tensões Residuais e Flechas em Soldas Planas de AISI 1020 Através de Ensaios de Tração, Microdureza Vickers e Mediçõees por Passe
(Universidade Federal do Pará, 2014) SANTOS, Carlos Augusto Cayres; FUJIYAMA, Roberto Tetsuo
Temperature in the Heat Affected Zone (HAZ) changes according to its position, with time, and cooling conditions during solidification. This variation in temperature can produce phase changes along the crystalline structure and thermal dilatations that originate welding residual stresses. In this work, deflection per passes was analyzed with height measurements, residual stresses in Base Metal (BM) were analyzed with tension tests, in the Heat Affected Zone (HAZ) and Fusion Zone (FZ). The variation through-thickness inside the Heat Affected Zone (HAZ) region was evaluated using Vickers microhardness tests for four different welds: the first one without restraints, the second fully restrained, the third with parallel restrictions on the weld bead, and the fourth with perpendicular restrictions to the weld bead. The results for each weld allowed modeling the deflection through linear adjustments, determining the stress profile according to the type of restraints adopted, the region in which the welded joint shall fail, and identifying regions that present beneficial or harmful stresses according to the type of restrictions and loading. The study concluded that deflection can be mathematically modeled as a welding pass function, and residual stresses observed in the HAZ and Fusion Zone (FZ) increase through thickness.
Aplicação do Óleo Vegetal de Andiroba (Carapa Guianensis) como Fluido Isolante Dielétrico em Transformadores de Distribuição de Energia
(Universidade Federal do Pará, 2014) PINTO, Vagner Barroso; FUJIYAMA, Roberto Tetsuo
The energy industry faces operational, technological, economic, and environmental challenges, requiring sustainable and efficient solutions. This study aims to verify the technical feasibility of applying andiroba vegetable oil (Carapa guianensis) as a dielectric insulating fluid in power distribution transformers. The physicochemical and dielectric properties of andiroba oil were analyzed and compared with commercial vegetable insulating fluids and mineral oil. The results indicate that andiroba oil has characteristics within the limits established by the ABNT NBR 15.422 standard, although specific treatments are needed to meet other specifications. It is concluded that andiroba oil is a viable and sustainable alternative to replace mineral oil in transformers, contributing to the economic and environmental development of the Amazon region.
BIOCOMPÓSITO DE POLIÉSTER REFORÇADOS COM A FIBRA DA FOLHA DE LICURI (Syagros coronata)
(Universidade Federal do Pará, 2014) SANTOS, Manfrine Silva; FUJIYAMA, Roberto Tetsuo
The northeastern hinterland is endowed with rich flora and abundant thus making a major supplier of plants provides the development of new polymeric composites. This dissertation aimed to the evaluation of the mechanical properties of composites reinforced by polyester fibers Licuri using a whole manual process, in order to provide the making of the material with the lowest possible technological level, thus becoming a totally viable material. The fibers were randomly dispersed in the composite, and the matrix used was pre-accelerated terephthalic polyester with cobalt naphthenate and cured at room temperature with methyl ethyl ketone peroxide (MEK) in a ratio of 0.33% (v / v). The results showed that the tensile strength increased with fiber length (5mm - 13.47 MPa, 10mm - 14.5 MPa and 15mm - 16.97 MPa), demonstrating that the investigated composites are potentially viable.
Controle de Qualidade através de Ensaios Não Destrutivos por Líquidos Penetrantes em Peças Componentes de Motocicletas Soldadas Novas e Usadas
(Universidade Federal do Pará, 2014) PAIS FILHO, Estevam Ferreira; FUJIYAMA, Roberto Tetsuo
Nondestructive Testing (NDT) by Liquid Penetrant (LP) is an important tool for quality control of materials, widely used in industry. This work aimed to study the behavior of NDT by LP applied to quality control in component parts of motorcycles, welded new and used. The study was developed in four companies of the automotive two-wheeler segment in Latin America. After a literature review, comparative tests were performed on new and used parts, identifying factors that influence the results. It was concluded that used parts may present surface changes and retention of contaminants, requiring greater care in the cleaning and removal of the penetrant liquid. The probability of false indications increases in welded used parts, suggesting a differentiated approach for these cases.
Controle de Qualidade no Processo de Soldagem de Componentes BGA no Processo de Fabricação de Placas de Notebook
(Universidade Federal do Pará, 2014) COSTA, Robson Marques; FUJIYAMA, Roberto Tetsuo
In recent years, companies have invested in technological improvements to add lightweight, reduced size, and high performance to products, aiming to meet global demand. This dissertation aims to conduct a study on the quality and reliability of the Reflow soldering process of BGA (Ball Grid Array) technology components in the manufacturing of notebook boards. Using qualitative and quantitative methods, tests such as Cross Section and Dye and Pry were conducted to evaluate the soldering quality. The results showed that the Reflow soldering process meets the acceptability criteria of international standards, indicating that the process quality can reflect better cost conditions and competitiveness for the investigated organization.
Diagnóstico de los factores microestructurales en el proceso de soldadura MIG/MAG que causan averías en los transformadores: estudio de caso
(INSTITUTO DE TECNOLOGIA, 2012) LOPES, Raimundo Valdan Pereira; COSTA, Otávio Fernandes Limada; FUJIYAMA, Roberto Tetsuo; PINTO, Vagner Barroso; LEITE, Jandecy Cabral; MAGALHÃES, Edilson Marques
The study examined microstructural factors in the MIG/MAG welding process of 3 mm and 4 mm industrial steel, leading to failures in 500 KVA power transformers. Charpy-V impact tests and microstructural analysis were conducted to correlate microstructure with impact toughness. Results revealed impurities in the weld pool, affecting weld quality and causing leaks of insulating oil.
Estudo da Influência da Umidade e Salinidade em Material Compósito de Matriz Polimérica
(INSTITUTO DE TECNOLOGIA, 2013) SANTOS, Eduardo de Jesus Silva dos; TAKAHASHI, Rafael; COSTA, Delbson Silva da; LOPES, Raimundo Valdan Pereira; PINTO, Vagner Barroso; LEITE, Jandecy Cabral; FUJIYAMA, Roberto Tetsuo; Prof. Dr. Carlos Tavares da Costa Júnior
This study examines the mechanical properties of polyester matrix composites reinforced with macaranduba wood powder and the effects of exposure to adverse environmental conditions, such as humidity and salinity. The results indicate that aging in water and saline water significantly reduces the impact resistance of the material due to degradation at the matrix-reinforcement interface.
Estudo das Propriedades Mecânicas de Biocompósito de Poliéster Reforçado por Fibra de Munguba (Pseudobombax munguba)
(Universidade Federal do Pará, 2014) LOPES, Raimundo Valdan Pereira; FUJIYAMA, Roberto Tetsuo
The diversity of Amazonian flora makes the region conducive to the development of new polymer composites. This study evaluated the mechanical properties of polyester composites reinforced with short munguba fibers, randomly arranged, using the lowest possible level of technological processing. The polyester matrix used was pre-accelerated terephthalic with cobalt naphthenate, cured at room temperature with methyl-ethyl-ketone peroxide (MEK). Munguba fibers were manually extracted from native adult trees in the Curarí floodplain region, Amazonas. The composites were characterized through tensile tests and microstructural analysis. The results showed that tensile strength increased with fiber length (5mm - 9.61 MPa; 10mm - 12.16 MPa; 15mm - 19.91 MPa), with better alignment and uniformity of the fibers in the matrix.
Estudo de la aplicación de aceite vegetal de Andiroba (Carapa guianensis) como un aislante eléctrico
(INSTITUTO DE TECNOLOGIA, 2012) PINTO, Vagner Barroso; FUJIYAMA, Roberto Tetsuo; LIMADA, Otávio Fernandes; LEITE, Jandecy Cabral; LOPES, Raimundo Valdan Pereira; MAGALHÃES, Edilson Marques
The study assessed the technical feasibility of andiroba oil (Carapa guianensis) as a dielectric insulating fluid (OVI) in transformers, comparing its physicochemical and electrical properties with commercial vegetable oils (Biotemp®, Envirotemp® FR3™) and mineral oil (OMI-1). Results showed that andiroba oil met density and viscosity limits per ABNT NBR 15422 standards and exhibited no corrosiveness. However, neutralization treatments were required to reduce acidity and water content (from 1306 ppm to <200 ppm). Dielectric strength (10.5 kV) and loss factor (12.5%) were below standards, indicating the need for adsorptive processes to enable industrial application.
ESTUDO DO PROCESSO DE SOLDAGEM DE CONECTORES HDMI EM PLACAS DE NOTEBOOK
(Universidade Federal do Pará, 2014) VIEIRA, Antonio da Silva; FUJIYAMA, Roberto Tetsuo
Derived from broader studies on improvements in the manufacturing processes of electronic products and computer hardware, this research aims to technically evaluate the weldability quality of the HDMI connector in the soldering process of Printed Circuit Boards (PCB) in notebooks. The study seeks to meet international acceptability criteria related to the solder fill of terminal components using Pin Through-Hole (PTH) technology, as specified in the IPC-A-610D standard. For the development of this research, the PDCA (Plan, Do, Check, Action) method was adopted, commonly used as a tool for problem-solving and continuous improvement in various industrial sectors. The analysis using X-ray inspection and metallographic cross-section tests demonstrated that the HDMI connector soldering process using reflow soldering showed better quality than manual soldering, ensuring product reliability. Based on the results achieved, the company in this study replaced manual soldering with SMT technology, employing the Pin in Paste (PIP) and reflow soldering processes.
Estudo do Processo de Soldagem de Conectores HDMI em Placas de Notebook
(Universidade Federal do Pará, 2014) VIEIRA, Antonio da Silva; FUJIYAMA, Roberto Tetsuo
Derived from broader studies on improvements in electrical and electronic manufacturing processes and computer goods, this research aims to technically evaluate the quality of weldability of the HDMI connector in the soldering process of Printed Circuit Boards (PCB) of notebooks, aiming to meet international acceptability criteria related to solder keg filling for Pin Through-Hole (PTH) component terminals as specified in the IPC-A-610D standard. For the development of the research steps, the Plan, Do, Check, and Action (PDCA) method was adopted. The results obtained through X-ray analysis and metallographic cross-section testing demonstrated that the quality of the HDMI component soldering through the reflow process, instead of the manual soldering process (hand soldering), meets the international IPC-A-610D standard, ensuring product reliability. Based on the results achieved, the company under study stopped performing manual soldering for this type of component in all notebook products, switching to soldering through SMT technology using the Pin in Paste (PIP) and Reflow soldering processes.
Gestão da Manutenção como Ferramenta de Controle de Qualidade na Indústria de Duas Rodas
(Universidade Federal do Pará, 2014) RIBEIRO, Ronei Nunes; FUJIYAMA, Roberto Tetsuo
This work presents the importance of using quality management tools in Hidden Amazon company (HDAM), for managing continuous improvement in its production process. It thus explains that the continuous improvement of products and processes within enterprises is essential, so it is possible to remain on the market, with a view to competitiveness in a globalized market today. For these improvements to occur, it requires the use of some methods and tools, which are logic-sequence for achieving the desired goals. The study brings in its contribution the convenience and simplicity of quality management tools and the PDCA cycle (Planning, Implementation, Verification and Action / Practice), an English acronym, who for various reasons are used in the various organizational levels of business same business segment in question. At the conclusion of that study, the results achieved with the implementation of the tools and the gains of the goals achieved are shown.
Materiais compósitos de matriz poliéster reforçados com resíduos de madeira de diferentes morfologias
(INSTITUTO DE TECNOLOGIA, 2013) LOPES, Carlos Eduardo Pinto; PEREIRA, Léo César de Oliveira; COSTA, Deibson Silva da; LOPES, Raimundo Valdan Pereira; PINTO, Vagner Barroso; LEITE, Jandecy Cabral; FUJIYAMA, Roberto Tetsuo; MAGALHÃES, Edilson Marques
This study presents the production and characterization of polyester matrix composites reinforced with residues from the Amazon timber industry. Using Angelim Pedra wood powder in different particle sizes and weight fractions (6.86% and 10.86%), the composites were evaluated for their mechanical properties through tensile tests. The results showed that smaller particles increase tensile strength, indicating that the reuse of these residues is viable and contributes to industrial sustainability.
Material Compósito de Matriz Polimérica Reforçada com Fibras Vegetais de Curauá e Sisal
(INSTITUTO DE TECNOLOGIA, 2013) SANTOS, Eduardo de Jesus Silva dos; TAKAHASHI, Rafael; COSTA, Deibson Silva da; LOPES, Raimundo Valdan Pereira; PINTO, Vagner Barroso; LEITE, Jandecy Cabral; FUJIYAMA, Roberto Tetsuo; MAGALHÃES, Edilson Marques
This study evaluated the manufacturing process of polymer matrix composites reinforced with natural curauá and sisal fibers, focusing on a fiber length of 25 mm. The methodology involved producing prepregs by spraying polyester resin diluted in styrene and manual lamination followed by compression molding. Specimens were tested according to ASTM D3039, showing that the curauá fiber composite exhibited higher tensile strength (average of 680.72 N) compared to sisal (431.53 N). The results confirmed the feasibility of the process and the influence of fiber type and length on the mechanical properties of the material.
Matrix polyester composite strengthened by munguba fiber (Pseudobombax munguba) Amazon
(INSTITUTO DE TECNOLOGIA, 2015) LOPES, Raimundo V. P.; LEITE, Jandecy C.; FUJIYAMA, Roberto Tetsuo; AFONSO, Marcus R. B.; HERMENEGILDO, Eleodoro R.; MAGALHÃES, Edilson Marques
The diversity of Amazon flora supports the development of new polymeric composites. This article evaluates the mechanical properties of polyester composites reinforced with short and continuous munguba fibers (Pseudobombax munguba). Tensile tests were conducted for fibers of different lengths (5, 10, and 15 mm) and continuous aligned fibers. Results indicated increased tensile strength with fiber length and superior mechanical performance with aligned continuous fibers.
Poliéster Reforçado por Fibras de Tauari (Couratari guianensis) Curtas e Contínuas e Alinhadas
(Universidade Federal do Pará, 2014) GOMES, Rilmar Pereira; FUJIYAMA, Roberto Tetsuo
Currently, engineering is vigorously investing in the search for natural materials to reduce the environmental impact caused by non-degradable materials. This work aims to develop polyester composites reinforced with Tauari (Couratari guianensis) fibers, both short and randomly arranged in the matrix, and continuous and aligned. The Tauari fiber is extracted from the bark of a tree found in various regions of Brazil, especially in the municipality of Itacoatiara, in Amazonas. The manufacturing process was carried out manually, using silicone molds without pressure, without a release agent, and at room temperature. The tensile test results showed that composites with 10 mm and 15 mm short Tauari fibers achieved mechanical strengths of 18.84 MPa and 19.08 MPa, respectively, while composites with continuous and aligned fibers of 250 mm reached 19.20 MPa.
Study of Quality and Reliability of Welding Process Reflow Component Technology BGA
(INSTITUTO DE TECNOLOGIA, 2015) COSTA, Robson Marques; LEITE, Jandecy Cabral; VIEIRA, Antonio da Silva; LOPES, Raimundo Valdan Pereira; FUJIYAMA, Roberto Tetsuo; Prof. Dr. Carlos Tavares da Costa Júnior
This study analyzed the quality and reliability of the BGA component Reflow soldering process in notebook motherboard manufacturing. Using a qualitative-quantitative approach via case study methodology, cross-section and X-ray analyses were conducted to evaluate alignment, cracks, and voids. The findings confirmed compliance with international standards IPC-A-610E and IPC-7095B, indicating the process is reliable and cost-effective for industrial application.
Vantagens da Aplicação de Material Compósito em Substituição às Ligas Metálicas na Aviação
(Universidade Federal do Pará, 2014) BARROS, Marcelo André Santiago; FUJIYAMA, Roberto Tetsuo
This paper shows the advantages of applying composites in aircraft structures, mainly in reducing weight, operating costs, and environmental, social, and economic impact. Through documentary research and experimental comparison between composite and metallic alloy aircraft, the efficiency and performance gains are highlighted, along with the new applications of composite materials in air transport and their influence on the global economy.