Extended Moment Tensor Inversion for Fracture Mechanism of Cracks Using Energy of Acoustic Emission Waveforms

Abstract

The acoustic emission (AE) technology is commonly used for detecting cracks in aircrafts, and the moment tensor inversion is an advanced signal post-processing methodology for quantitatively calculating fracture mechanism. The inversion accuracy of the traditional inversion approach is significantly dependent on precisely recorded waveforms, which require high sampling frequencies of signal recording. For reducing the requirement of sampling frequencies, an extended inversion approach for moment tensors is proposed and the accumulated energy of the signals is used to invert for fracture mechanism. The synthetic tests show that the inversion accuracy of the new inversion approach is more stable for various sampling frequencies than that of the traditional displacement-based one. The inversion results calculated by the new approach are less sensitive to noise, and accurate results can be achieved by less sensors. Generally, the extended inversion approach can help evolve the structural health analysis of aircrafts significantly.