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TY  - THES
AU  - Wang, Ding
TI  - Damage and strain patterning simulation of structural heterogeneity
PB  - Rheinisch-Westfälische Technische Hochschule Aachen
VL  - Dissertation
CY  - Aachen
M1  - RWTH-2019-01925
SP  - 1 Online-Ressource (v, 131 Seiten) : Illustrationen, Diagramme
PY  - 2019
N1  - Veröffentlicht auf dem Publikationsserver der RWTH Aachen University
N1  - Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2019
AB  - Structural heterogeneities arise in most metallic materials on the microscopic scale prior or after deformation. On the one hand such heterogeneities have great potential to achieve specific properties for high strength and lightweight applications, but on the other hand the ductility and toughness of materials could be critically reduced by damage initiation which is promoted by such heterogeneities. In this thesis, the effect of individual microstructure features and underlying dislocation interactions on mechanical and/or damage responses of materials were investigated by systematic simulation studies. Crystal plasticity Fast Fourier transformation simulations were conducted to gain deep insights into the complex interactions between individual microstructural and micromechanical mechanisms in heterogeneous structures. Two subjects were studied in this thesis: the first is the particle-induced damage in Fe - TiB2 metal matrix composites steels and the second is the formation of laminate deformation patterning in nickel single crystal. Fe - TiB2 metal matrix composites, termed high modulus steels due to their high specific stiffness, have great potential for lightweight design applications. However, the toughness of these steels is critically reduced by the presence of the brittle TiB2 particles. Due to the multitude of parameters affecting microstructural damage, experimental studies are complex and inefficient to identify the impact of particle microstructure on fracture toughness. In this thesis, a computational simulation approach to derive guidelines for optimizing the mechanical properties of high modulus steels was conducted. Key microstructural parameters such as particle clustering degree, size and volume fraction were investigated. Model geometries were statistically and systematically generated with varied particle configurations from random to clustered distributions. Simulations were then performed using a crystal plasticity Fast Fourier Transformation simulation method coupled with a novel phase field damage model. The effect of individual particle parameters on particle damage revealed that microstructures with homogeneous particle distributions of 7 15
LB  - PUB:(DE-HGF)11
DO  - DOI:10.18154/RWTH-2019-01925
UR  - https://publications.rwth-aachen.de/record/755595
ER  -