Mg-5Y-4Nd alloy and Mg-5Y-4Nd/SiC metal matrix composite were deformed at ambient temperature. Acoustic emission was measured during deformation.
The time dependence of the count rate was measured with the two levels of discrimination. Pronounced maximum was observed at the onset of plastic deformation.
It was ascribed to massive twinning and glide of dislocations in the alloy. In the composite, the AE activity was lower in comparison with the alloy and two acoustic emission peaks were detected.