A new method to assess the ultrasonic attenuation in samples with non-distinguishable echoes

The progressive energy loss experienced by the signals as they propagate through the material is mainly due to two mechanisms: energy absorption and scattering. Attenuation is usually measured from the echoes observed on the A-scan which originates from reflections in the material. This paper describes a new method of quantifying the attenuation of ultrasonic waves in samples whose nature makes it impossible to distinguish reflections.The attenuation is quantified in terms of the time taken to receive the energy, expressed as a multiple of the time of flight TOF (n·TOF). The method starts from the A-scan data taken from the moment at which the signal begins to be received until its complete attenuation. The received energy is related to the square of the amplitude of the ultrasonic wave. This value of the energy is plotted versus n·TOF, noting the values of n times the TOF at which 10%, 20%, …, 90% of the total energy received are reached.The paper includes a checking of the method by its use in different specimens (cubic samples of granite and raw samples of pork loins). The results show interesting relationships between the new attenuation values and other non-ultrasonic parameters of the specimens.The progressive energy loss experienced by the signals as they propagate through the material is mainly due to two mechanisms: energy absorption and scattering. Attenuation is usually measured from the echoes observed on the A-scan which originates from reflections in the material. This paper describes a new method of quantifying the attenuation of ultrasonic waves in samples whose nature makes it impossible to distinguish reflections.The attenuation is quantified in terms of the time taken to receive the energy, expressed as a multiple of the time of flight TOF (n·TOF). The method starts from the A-scan data taken from the moment at which the signal begins to be received until its complete attenuation. The received energy is related to the square of the amplitude of the ultrasonic wave. This value of the energy is plotted versus n·TOF, noting the values of n times the TOF at which 10%, 20%, …, 90% of the total energy received are reached.The paper includes a checking of the method by its use in different...