Métodos de propagação de ondas ultrassonoras visando a estimativa de propriedades mecânicas de madeiras amazônicas

Abstract

This study has as objective evaluate the different methods of propagation of ultrasonic waves, seeking estimate the mechanical properties of resistance and rigidity of ten Amazonian woods, these being: Hymenolobium petraeum Ducke. (Angelim-Pedra), Trattinnickia burserifolia Mart. (Amescla), Qualea paraensis Ducke. (Cambará), Ocotea velutina Mart. (Canelão), Erisma uncinatum Warm. (Cedrinho), Dipteryx odorata (Aubl.) Willd. (Cumaru), Apuleia Ieiocarpa (Vog.) Macbr. (Garapeira), Mezilaurus itauba (Meisn.) Taub. (Itaúba), Hymenaea courbaril L. (Jatobá). The proof bodies were made by dimensions of 5 x 5 x 20 cm (thickness, width and length), being it larger in the axial direction. The samples were submitted to two methods for determining the technological properties, by means of nondestructive methods (Propagating ultrasonic waves) and destructive (parallel compression test). Within the non-destructive methods was evaluated three methods of propagating ultrasonic waves (direct methods, semi direct and indirect). According to the results, although the values of the static and dynamic modulus of elasticity and dynamic show different values, the ultrasound may be used efficiently form, fast and effective for determining the technological properties of the wood. The method of direct application obtained by ultrasound showed the best results, proving to be the best way to characterize mechanically the timber.