抄録
This paper reports the mechanical effect produced in the pig's thigh meat and human finger by the ultrasonic insonation. When the pig's thigh meat is compressed by an increasing weight and vice versa, ultrasound insonation yielded the strain wave with the differently depressed waveform with respect to the positive and negative amplitudes. This suggested the non-reversible deformation and the stress-strain hysteresis. This phenomenon is analogous to the parasitic oscillation in the metal plate with micro-cracks. In case of intense sound insonation, the sample showed the existence of spike-like stress. This effect was computed with the RPNNP equation for a single bubble motion. The result coincided with the experimental event and manifested that the repulsive force via the liquid from the bubble approached the 10 M Pa for the incident sound with a pressure amplitude of 100 k Pa.
