Ultrasonic Measurements In Brazilian Hardwood

This paper reports on a study of the application of ultrasound waves in wood with the purpose of evaluating the latter's mechanical properties. The evaluation is based on the correlation between the speed of sound, modulus of elasticity and density. The speed of transmission is sensitive to the material's quality-determining factors; hence, this technique is an important industrial tool to improve the quality control of processes. The species used in the experimental procedure were "cupiúba" (Goupia glabra) and "jatobá" (Hymenaea sp). Tests were carried out to determine the properties of apparent density at 12% humidity content (rhoap,12%), modulus of elasticity in static deflection (E M), and modulus of rupture (MOR). Ultrasound tests were also performed to find the stiffness matrix coefficient (C LL), for purposes of comparison with the static findings. The results and analyses lead us to conclude that the nondestructive ultrasound method can be employed to obtain reliable evaluations of the mechanical properties of dicotyledons