An investigation of the acoustic emission generated from silicon particles in aluminum-silicon alloys.

摘要

Acoustic Emission generated during tensile deformation of Al-Si alloys has been measured and characterized. Two distinct acoustic emission maxima have been observed. Yield stress was found to decrease with the annealing of Al-Si alloys and RMS voltage at yield increase. The yield phenomenon is well explained by the dislocation model.;The acoustic emission at strains well pass yield was found to depend on silicon concentration and heat treatment. The only sources of the acoustic emission are decohesion of silicon particles from the matrix and fracture of silicon particles. Fracture of silicon particles produces high amplitude signals which can be well described by present theoretical prediction. Acoustic emission from decohesion of silicon particles from the matrix have lower energy. A series of discussion has been carried out from different points of view.