Measurement of acoustic attenuation coefficient of material with the stepped sample
LIU Xiaorong1, HE Xiping1*, CUI Dong1, HE Shengping2, NI Tao2, CHEN Rensong2
(1 School of Physics and Information Technology, Shaanxi Normal University, Shaanxi Key Laboratory of Ultrasonic, Xi′an 710119, Shaanxi ,China;2 11 Subbox, 150 Mailbox, Baoji 721013, Shaanxi, China)
Abstract:
In order to measure the acoustic attenuation coefficient more precisely, the influence of acoustic reflection and acoustic transmission at the upper and lower interfaces of a material are considered.The expression of acoustic attenuation coefficient is derived strictly.The traditional test sample is changed into a stepped one.With the improvement of one tested echo into two tested echoes at the thinner and thicker ends of the stepped sample, the pressure ratio before and after attenuation can be obtained.Thus the precise acoustic attenuation coefficient of the material is available.Since the acoustic attenuation induced by reflection and transmission is excluded,the acoustic attenuation coefficient measured by such methed is reduced 25% comparing with traditional methed.
KeyWords:
acoustic attenuation; stepped sample; pulse reflection method
