A Study of the Sound Properties of Picea Abies Wood by Using (NDT) Ultrasound Test

The goal of this research is to study the ultrasound wave parameters such as velocity and attenuation in Picea abies species. To that end, two varieties of this species were selected For Ujavbit Woods in Kelardasht, Maznadarn Province. To prepare samples, discs in 5 cm thickness were prepared in the three types of with bark, without bark and defected (handmade hole) to be used in measuring ultrasound wave parameters. In this research, the measurement technique used was direct contact with 55 KHz frequency. The results of the test showed that the tree bark increases wave attenuation coefficient intensively while it has no significant effects on wave velocity. The result also suggested that the defects (artificial hole) in Picea abies species disc had the highest effects on ultrasound wave velocity parameters and decreased it sharply; however, it has no significant effects on wave attenuation coefficient.