Analiza sygnału emisji akustycznej z korowej tkanki kostnej obciążanej do złamania

Acoustic emission signals (AE) were recorded during the bending test of rat femora. Bones from two adult age groups were tested: five month (A-5) and 12 months old (A-12). Bones were loaded to fracture in three-point bending. Energy of AE, number of bursts and average energy for one burst were analyzed to maximum force and to final fracture. Qualitative and quantitative differences in AE signals between two age groups were found in quasi-plastic range of deformation, while in the whole test the differences were not present. Number and energy of AE bursts in quasi-plastic range was larger in the older than in the younger bones. The fact was attributed to a larger amount of AE sources and a larger probability of growth of microfractures within the tissue before the final fracture load was achieved. The data confirm that brittleness of healthy, mature bone tissue increases with age.