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Waste Foundry Sands (WFS) are by-products of the steel industry due to the foundry process. The residual material can be used in civil construction as an aggregate because of its mineral origin. This paper aimed to characterize the WFS obtained at two sources, using laboratory tests that are regularly required in highway engineering specifications.  The laboratory program showed that the tests results satisfy the main specifications in Brazil. Laboratory tests results also show that WFS has characteristics that are similar to the manufactured sand that is usually used in asphalt pavement construction. It is concluded that the WFS could be used in asphalt pavement projects, as a subgrade reinforcement, sub-base or base layer and in asphalt wearing courses.

Coatings are used to promote the thermal protection of metal alloys. In the aeronautical industry, the coatings used to protect the turbine blades are called Thermal Barrier Coatings (TBC). The use of NiCrAlY is an alternative as a bonding layer in coatings for turbine blades and it is possible to increase its useful life. This work aims to study the metallurgical bond between the 316-stainless steel substrate and the NiCrAlY coating which was sprayed through the High-Velocity Oxygen-Fuel (HVOF) and after irradiated by a CO2 laser beam with power of 125 W and speed of 50 mm/s. The samples were characterized by scanning electron microscopy (SEM) and the semi-quantitative analysis energy dispersive spectroscopic (EDX) showed that the chemical composition of the coating and the substrate have maintained its original stoichiometry. The line scan analysis is a technique of the EDX to analyze the diffusion between the main chemical elements of 316 steel and NiCrAlY and X-ray diffraction by identifying the alumina AL2O3 phases on the sample surface and the results showed the metallurgical bond between substrate and coating.

A sustentabilidade na construção civil objetiva a redução de desperdícios, impactos ambientais e integração do empreendimento com o meio ambiente, sendo que o reuso de resíduos industriais não perigosos como agregado é uma solução que contribui para a sustentabilidade. Neste contexto, o objetivo deste artigo é demonstrar a viabilidade técnica e econômica da reutilização do resíduo industrial Areia Descartada de Fundição (ADF), como agregado em artefatos de cimento. Para tanto, a ADF foi caracterizada segundo as metodologias para agregados da construção e foram produzidos lotes de artefatos de cimento contendo 33 % de ADF (em massa). Para estimar a economia direta do reuso em USD/t, foram propostos dois modelos matemáticos. Os resultados mostraram a viabilidade técnica em relação às normas da Associação Brasileira de Normas Técnicas (ABNT) para agregados e artefatos de cimento, e uma economia proporcionada da ordem de 1 a 10 %, além de impactos positivos na cadeia de produção e descarte de ADF.

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