Vinícius Martins

ESTUDO DO COMPORTAMENTO DO ALUMÍNIO (Al) COM ADIÇÃO DE 1% COBRE (Cu) OBTIDO PELA METALURGIA DO PÓ CONVENCIONAL

Powder metallurgy is a mechanical forming process with increasing applicability in the Brazilian industrial scenario. Application fields include, for example, manufacturing of automotive components, home appliances, cutting tools and electric tools. Sintering is the most important phase of the process, in which the already compacted powder is subjected to a temperature below its melting point, obtaining a material with excellent finish, dimensional accuracy and mechanical properties. The present work aims to assess the behavior of aluminum with the addition of 1% Copper, specifically evaluating density, hardness and metallography presented as a function of applied loads on each of the samples was between 100 MPa to 1,000 MPa. The metallography presented porosity inherent in the process, but there was a hardness increase from 40 to 50 HV. Keywords: Powder metallurgy, Aluminum Copper composition, hardness, density and metallography.

Awareness of children about rational use of water: an approach basing on serious game

The water shortage expectation in a near future proves that the world population must be mobilized, as soon as possible, to face the problem of the water waste in daily activities. This paper presents the development of a web serious game to teach children about that problem which already affecting lives of many people around the world. We believe that education could be the better tool to change cultural habits and, in this way, the bigger awareness and a better use of hydric resources.

Análise das 7 perdas de Shingo em ambientes de aprendizagem

Technical schools have dynamic systems that provide the student’s maximum contact with the technology. Activities which are not connected to this interaction and students’ downtime mean losses in the teaching-learning process. The Toyota Production System (TPS), however, is a production engineering philosophy that prioritizes the losses minimization. The objective of this study is to assess and minimize losses in the teachinglearning process in a technical school, using the concepts of the 7-losses of Shingo within the TPS. By conducting a diagnosis for a survey and measurement of losses, actions were filed in order to minimize them. Four losses were identified. With simple changing actions in the layout, significant improvements were obtained in the losses related to the wait, movement and transportation.

Ring test for evaluation of behavior of the friction coefficient of aluminum alloy

O objetivo deste trabalho e realizar um estudo comparativo sobre a influencia de lubrificantes no coeficiente de atrito da liga de aluminio AA6351. O atrito tem um efeito significativo na deformacao do material, alterando a forca de compressao e o desgaste da matriz e da peca. A escolha de um lubrificante com eficiencia na reducao do atrito da interface peca/matriz aumenta a vida util da ferramenta e, consequentemente, melhora a margem de lucro quando em producao industrial. Para o forjamento de ligas de aluminio, recomendam-se lubrificantes a base de grafite e agua ou grafite e oleo. Neste estudo, tres lubrificantes comerciais foram testados: grafitado ( Aerodag G ), sintetico ( Synd Forg 100-A ) e um a base de oleo ( Dechelub 5562 ). A metodologia adotada: obtencao de corpos de prova, ensaio do anel em prensa hidraulica variando-se os lubrificantes, simulacao em programa computacional para aquisicao das curvas de calibracao e comparacao dos resultados. Comparando os dados experimentais com as curvas obtidas por simulacao foi verificado que, entre os tres lubrificantes testados, o sintetico obteve o melhor desempenho, seguido do lubrificante a base de oleo. O lubrificante a base de grafite obteve um desempenho inferior para essa aplicacao. Palavras-chave: aluminio, atrito, simulacao computacional e lubrificacao.

Effect of addiction of Nb, Mo, Cr and Ti on the microstructure of WC-6Co

Hard metals are a group of materials known as sintered composites involving hard phases (carbides) with a metallic phase, being widely used in applications where you want high hardness and wear resistance combined with high toughness. This article presents the results of adding 1% by weight of the elements Nb, Ti, Cr and Mo on the microstructure of the hard metal from a commercial composite of WC-6Co. In this composite was added 1.5% (by weight) of zinc stearate as lubricant and sintered at a temperature of 1450oC in an atmosphere of argon. Aiming to analyze the product efficiency was held on micro structural characterization through the testing of green density, shrinkage, sintered density, microstructure and microhardness. Key words: hard metal, carbide, balancing mass, powder metallurgy, sintering.

Influence of the bismuth on mechanical properties of high speed steel AISI M2 sintered

A adic ao de bismuto em uma liga de aco AISI M2 produzida por metalurgia do po foi avaliada, buscando melhorar a usinabilidade e as propriedades mecânicas deste material. Para este estudo, foram analisadas as amostras de aco rapido AISI M2 com os seguintes teores de bismuto: 0.1%, 0.3%, 0.5% e 1%. O processo de conformacao do po realizou-se atraves da compactacao uniaxial a 600 MPa e sinterizacao sob atmosfera protetora de 95%N2 + 5%H2. A temperatura de sinterizacao utilizada foi de 1.130°C. As amostras apresentar am um aumento proporcional da porosidade com o acrescimo percentual de bismuto. No ensaio de desgaste e de compressao a amostra de 0,3% de bismuto apresentou menor resistencia mecânica. No ensaio de usinabilidade as amostras de M2 e a M2 com 1% de bismuto The addition of bismuth in an alloy steel AISI M2 produced by powder metallurgy, has been evaluated aiming to improve the machinability and m echanical properties of this material. For this study, were analyzed samples of AISI M2 steel quick with the following levels of bismuth: 0.1%, 0.3%, 0.5% and 1%. The process of shaping the powder was carried out by uniaxial compaction at 600 MPa and sinte ring in protective atmosphere of 95% N2 + 5% H2. The sintering temperature used was 1130 ° C. The samples showed a proportional increase of porosity with increasing percentage of bismuth. In the test of wear and compression of the sample of 0.3% of bismuth showed lower mechanical strength. Machinability testing of the samples of M2 and M2with 1% of bismuth sintered obtained chips shear (in the form of needle) and chip block (as arcs), respectively.