Acoustic emission in compressed nanocrystalline Mg and Al alloys and composites


Project start:01.01.2007
Project end:31.12.2009
Programme:Academic agreement
Institute position in the project:Project co-lead partner
Project leader at the institute:Stanislav Kúdela Sr.
The aim of the project is to investigate the relation between the mechanical properties and acoustic emission (AE) in nanocrystalline both Mg and Al alloys obtained by the ECAP technique (Equal Channel Angular Pressing) as well as in composites reinforced with ceramic fibres and also with carbon nanotubes. The alloys and composite samples (prepared at IMMM SAV in Bratislava) will be subjected to ECAP operation and next to channel-die compression (at IMMS PAS in Kraków) with simultaneous registration of the AE parameters. The investigations are focused on the following problems: * Deformation mechanisms in nanocrystalline materials, plastic and superplastic flow, slip on the grain boundaries and their role in the microcracking processes and the relation to the acoustic emission phenomenon * Measurements of the rate of AE events as a function of energy and/or frequency, acoustograms and spectral characteristics of AE, identification of strain mechanisms and monitoring of the microcracking by means of AE method. * Determination of the homogeneity of microstructure using ultrasound measurements (cooperation with IFTR PAS in Warszawa), microstructure evolution and its effect on the strength properties of nanomaterials.