Breakage mechanism in heterogenous structures – combining microstructure of EnAM and breakage / liberation behavior

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The overall idea is to generate a new process model, which combines information about the inner heterostructure of the EnAM-system containing e.g. partially amorphous structures to its macroscopic breaking probability. To understand the breakage event of the heterostructure of the EnAM-system, which consist of amorphous and crystalline phases, investigations with single particles from different batches of slag generation are conducted. The focus is on the meso- and microscopic effects during deformation and crack formation prior to the breakage event and as well as on the properties of the debris. The surfaces of the fragments provide information on the rupture of the atomic bonds within the composite matrix, the slag respectively. The elastic and plastic deformation of the intergrown slag containing several EnAM grains under compressible load provides information about the locally retained mechanical energy, which later on will lead to the material rupture. Three main experimental methods will be applied: in-situ load experiments with computer tomography (CT), AFM characterization of the breakage planes and statistical validation experiments with single compression testing. The experimental data is aggregated and analyzed to identify characteristic structural properties of the initial particle containing EnAM-grains as well as of the resulting debris of that particle after breakage. Using the CT-data the particle is virtually rebuilt from the debris in 3D, for that all breakage planes can be reconstructed. Comparing the breakage planes with he initial structure of the EnAM-sample we obtain a detailed view on the occurrence of transgranular or intergranular breakage. In microscale the AFM investigations provide information about the topology of the breakage planes, which gives a microscopic information of interacting geometries, which are the basis for the modelling in the 2nd FP. Based on the data analysis, a deeper understanding of the breakage event in the micro- and meso-scale is deducted, which results in a material and process model.