Supply chain risk management: An exploratory research in Brazilian aerospace industry

This paper aimed to analyse supply chain risk factors in aerospace industry. It was conducted an exploratory research at an important Brazilian aerospace company. This company has a major role at the global aerospace industry. Senior managers assessed risk factors such as quality, productivity, supply chain, business strategy, organisation, environmental and natural political, indicators, product management, and information system. Analytic hierarchy process was applied to prioritise these factors. The most relevant were quality and productivity. Copyright © 2011 Inderscience Enterprises Ltd.

Development of silicon carbide substrates for aerospace applications

Payload and high-tech are important characteristics when the goals are aerospace applications. The development of the technologies associated to these applications has interests that transcend national boundaries and are of strategic importance to the nations. Ultra lightweight mirrors, supports and structures for optical systems are important part of this subject. This paper reports the development of SiC substrates, obtained by pressing, to be applied on embedded precision reflective optics. Different SiC granulometries, having YAG as sintering additive, were processed by: ball milling, drying and deagglomeration, sift, uniaxial and isostatic pressing, and, finally, argon atmosphere sintering at 1900°C. Different porosities were obtained according to the amount of organic material added. Into one side of the samples pellets of organic material were introduced to generate voids to reduce the weight of samples as a whole. The substrates were grinding and polished, looking for a SiC surface having low porosity, as porosity is directly related to light scattering that should be avoided on optical surfaces. Laser surface treatments were applied (using or not SiC barbotine) as a method to improve the surface quality. The samples were characterized by optical and laser confocal microscopy, roughness measurements and mechanical tests. The results are very promissory for future applications. © 2012 Materials Research Society.

Estudo das propriedades de barreira de filmes depositados a plasma sobre a liga de alumínio 2024

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo do uso de ferramentas cerâmicas na usinagem de inconel 718

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Experimental RTM manufacturing analysis of carbon/epoxy composites for aerospace application

The success of manufacturing composite parts by liquid composite molding processes with RTM depends on tool designs, efficient heat system, a controlled injection pressure, a stabilized vacuum system, besides of a suitable study of the preform lay-up and the resin system choice. This paper reports how to assemble a RTM system in a laboratory scale by specifying heat, injection and vacuum system. The design and mold material were outlined by pointing out its advantages and disadvantages. Four different carbon fiber fabrics were used for testing the RTM system. The injection pressure was analyzed regarding fiber volume content, preform compression and permeability, showing how these factors can affect the process parameters. The glass transition temperature (Tg) around 203 ºC matched with the aimed temperature of the mold which ensured good distribution of the heat throughout the upper and lower mold length. The void volume fraction in a range of 2% confirmed the appropriate RTM system and parameters choice.

Utilização da mínima quantidade de lubrificante (MQL) com água no processo de retificação cilíndrica em cerâmica avançada com rebolo de ligante resino cerâmico/metálico

Pós-graduação em Engenharia Mecânica - FEB

Ultrasonic waves: Bioeffects on yeast cells

Applications of ultrasound were starting from 1912 with the primary objective the detection of icebergs on prevention of maritime accidents. Algae, fish deaths and destruction were observed in the vicinity of sonar that equipped ships and submarines during the First World War.The evolutions of research and studies with ultrasound have big advances following the discovery of piezoelectric transducers in science and technology. As an example we can mention its application in microsurgery, fatigue detection in aerospace mechanics, catalysis sonochemical, biotechnology and others.The work presented here aims to demonstrate the application of ultrasonic in pulsed mode beams in biotechnology with the aim of improving the fermentation of a culture broth containing biological agents. In these experiments we used as ultrasound equipment and oscilator Sonics VCX-600 (20KHz), probe type wave guide. The experiments were conducted in a glass reactor of 200 mL of biomaterial containing cane juice and Saccharomyces cerevisiae in suspension. The parameters analyzed were related to the content Alcohlic (FID gas chromatography), and cell viability (Neubauer chamber), TRS (refractometry). Analysis of results showed that the total production exceeded in irradiated samples compared to normal fermentation (without ultrasound), suggesting additional advantage of ultrasound activation. Lastin Trials 1400 min, showed ethanol production systems 12% more than non-enabled systems. In this context alternatives for ethanol production, bio fuel and many other byproducts of the alcohol industries and chemicals could benefit from the use of ultrasound beams in this range of frequencies.

Ensaios não destrutivos: metrologia e calibração

To perform the quality control of various industries like: petrochemical, nuclear, aerospace, steel, shipbuilding, pulp and paper, and inspection of welded products, castings, forgings, rolled products, among others, used the method of Non-Destructive Testing (NDT). The method is based on the physical properties of the material, so selecting a procedure more appropriate. The company Inter-Metro Serviços Especiais Ltda., with its cutting-edge laboratory, dedicated to the implementation of calibration services and measurement equipment for industrial, medical, occupational safety and Non-Destructive Testing (NDT). It has a trained team, providing guidance and providing support for improving procedures for testing and measuring

Um estudo sobre a preparação metalográfica da liga de aluminio AA7075-T6

The increasing technological innovation and demand for materials with better properties boosts research into new materials and new alloys. To do so, aluminum alloys are being developed, among them the AA7075-T6, having many applications in aerospace and military industries, machinery and equipment, molds for plastic injection and structures. To study and understand the properties, characteristics and especially the microstructure of the material, the metallographic preparation is essential. This paper presents new methodologies to achieve the metallography of samples of scrap alloy AA7075-T6, with emphasis on methods of polishing. For the five samples, the best results were those with specific grinding, the samples only going down on the sander. For polishing, the most effective method so far has been using the polishing cloth 16.3, of ATM enterprise, solution of diamond 3 μm, solution of diamond 1 μm, and colloidal solution of OP-S. For the etching, the reactive agent used was phosphoric acid (H3PO4) 85% P.A., as 90% in the proportion of distilled water to 10% acid. The best results were obtained in the attacks of 300 and 240 seconds, revealing the grain boundaries in most areas. Methodologies need more studies and more tests, but the results have proved to be satisfactory

Avaliação da colagem de suportes utilizados para fixar cabos elétricos em aeronaves

The most usual method to fix supports that hold the vast majority of electrical cables on an aircraft is accomplished by using, for this purpose, rivets. However, this procedure may some cause some inconveniences such as the need of effecting holes in the structure that is intended to fix these supports, thus decreasing resistance of the structure. In order to have an alternative to seek an increase in the performance of structured materials, the aircraft industry, like other industries, have been studying the use of collage as a method of replacing this usual forms. Against this backdrop, this paper aims to assess the strength and durability of a joint bonded using the adhesive EA9394, manufactured by company Henkel Corporation, and perform a careful survey of the mechanical performance of riveted structures, taking into account different types of conditioning environment and thus create a database that can be used by the aerospace industry

Editorial dynamics and control of aerospace and vertical transportation systems

This Special Issue presents a selection of papers initially presented at the 11th International Conference on Vibration Problems (ICOVP-2013), held from 9 to 12 September 2013 in Lisbon, Portugal. The main topics of this Special Issue are linear and, mainly, nonlinear dynamics, chaos and control of systems and structures and their applications in different field of science and engineering. According to the goal of the Special Issue, the selected contributions are divided into three major parts: “Vibration Problems in Vertical Transportation Systems”, “Nonlinear Dynamics, Chaos and Control of Elastic Structures” and “New Strategies and Challenges for Aerospace and Ocean Structures Dynamics and Control”.

Recycling residues from the pulp and paper industries in the civil construction

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)