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Wood offers a good combination of high strength and low density, but its complete characterization takes a long time. This study aimed to correlate apparent density, chemical component and porosity parameters with the physical and mechanical properties of the wood as an alternative route to reduce the time spent proposing equations to estimate each mechanical property. Ten tropical wood species were characterized in accordance with Brazilian Standards and chemical components were determined by the Klason method, and the porosity using mercury intrusion. Multivariate regression models were applied to the results of each species to find the relationships. Good results were obtained, such as the coefficient of determination and the analysis of variance, which indicated that the equations for 10 out of the 16 properties are significant. Therefore, the apparent density, chemical component and porosity parameters used reduce the time intervals much lower than the time test stipulated by the standard.

This study evaluates the effect of high N, Ni, and Ti contents on the microstructure and corrosion properties of a supermartensitic stainless steel when immersed in a 3.5% NaCl solution. Tempering procedure at several temperatures resulted in a martensitic microstructure composed of grains ranging from 60 to 70 μm, TiN microparticles, and austenite. The sample treated at 610 °C showed better corrosion resistance due to the lower current density of the anodic polarization curve and less negative pitting potential, which was thoroughly influenced by the content of austenite (6.2 vol%). Anodic curves presented current fluctuation attributed to the presence of passive film instability, due to micro‐galvanic corrosion between TiN particles and matrix. Impedance analysis on the sample tempered at 610 °C confirmed that 6.2 vol% of austenite assists the protective film by making it thicker and more protective in chloride media.

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