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The increase in economic and technological competitiveness means that the automobile industry seeks constant innovation in its production methods and processes, in order to produce lighter, safer and more efficient vehicles. Products with greater mechanical resistance, better conformability, thickness combinations of plates / materials are sought with a focus on reducing mass and increasing the rigidity of the vehicle body. In this scenario, Tailor Welded Blank (TWB), which is a top welding technique (by unconventional processes) of sheets of different specifications (materials, thicknesses and / or coatings), appears as a solution, as it allows localized distribution of mechanical properties, mass, optimizing the relationship between structural rigidity and the total weight of the vehicle body. The great challenge of this technique is to combine two processes with completely different demands, welding and mechanical forming. Due to the complexity of forming TWBs, the use of simulations has been widely adopted. In this review, different results of the numerical simulation methods used for a Tailor Welded Blank are compared, focusing on the details and the influence of the parameters used.

Iron aluminides are considered as candidate materials for high temperature applications for their excellent high temperature corrosion and oxidation resistance. In the present work, iron-aluminide coatings were developed by friction surfacing (6351 aluminum alloy deposited on a low-carbon steel substrate) followed by a diffusion heat treatment. The initial coatings were found to be geometrically homogenous and adhered well to the steel substrate. The heat treatment process was carried out at 550 °C for 48, 72 and 96 h and the resulting coatings were characterized in terms of microstructure, chemical composition, hardness distribution and phase composition. After heat treatment, the coating/substrate interface morphology was modified and presented patterns typical of Fe-Al intermetallic formation, as well as a substantial increase in hardness (>900 HV) relative to the initial as-deposited condition. With the diffusion treatment, initially Fe2Al5 was found to develop in the coatings, which was converted into FeAl2 after longer exposures.

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RESUMO Peças fabricadas com polímeros de alto desempenho têm sido substituídas por materiais similares, sendo produzidas com uma composição de polipropileno (PP), que tem um custo mais baixo. Uma das composições mais comumente utilizadas é a junção do polipropileno com fibras, resultando na formação de um novo material, com características diferentes às dos seus constituintes. Este tipo de junção é denominado compósito. O objetivo deste trabalho é avaliar o comportamento do compósito de polipropileno com fibra de vidro para a substituição do material da carcaça de um elemento filtrante fabricado atualmente com um compósito de nylon e fibra de vidro na proporção de 30% em peso. Foram injetados corpos de prova usando PP puro e com cargas de fibra de vidro nas proporções de 15%, 20% e 30%, a análise de comportamento, através de ensaio de tração, flexão, resistência ao impacto, dureza, índice de fluidez e determinação do índice de contração indicou o compósito PP com 30% de fibra de vidro com melhor comportamento. Posteriormente realizou-se a injeção da carcaça do elemento filtrante no compósito PP com 30% de fibra de vidro que passou por testes práticos.

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