Evaluation of the Evaluation of the C. Mercer 1, T. Speck2,3, 1 Research Center for Structural Materials, National Institute for Materials Science (NIMS), Japan M. Thielen3, J. Lee4 and D. S. Balint4 C. Mercer 1, T. Speck2,3, 2 Cluster of Excellence, Freiburg Center for Interactive Materials and Bioinspired Technologies, Germany 1 Research Center for Structural Materials, National Institute for Materials Science (NIMS), Japan 3 Plant Biomechanics Group, University of Freiburg, Germany 2 Cluster of Excellence, Freiburg Center for Interactive Materials and Bioinspired Technologies, Germany 4 Department of Mechanical Engineering, Imperial College London, United Kingdom 3 Plant Biomechanics Group, University of Freiburg, Germany 4 Department of Mechanical Engineering, Imperial College London, United Kingdom Functional lattice structures are designed to exhibit interesting properties not typically found in bulk single materials. Furthermore, despite often complex geometries, such structures can be successfully Functional lattice structures are designed to exhibit interesting properties not typically found in bulk fabricated via modern additive manufacturing methods. Two types of functional lattice are presented. single materials. Furthermore, despite often complex geometries, such structures can be successfully The first is designed to exhibit low thermal expansion behavior to mitigate the effects of thermal strains fabricated via modern additive manufacturing methods. Two types of functional lattice are presented. in applications such as hypersonic vehicles and space mirrors. The second type of structure is an auxetic The first is designed to exhibit low thermal expansion behavior to mitigate the effects of thermal strains (negative Poisson’s ratio) metamaterial which possesses excellent energy dissipation characteristics in applications such as hypersonic vehicles and space mirrors. The second type of structure is an auxetic during impact. In both cases, the mechanical response of the structures is evaluated experimentally. (negative Poisson’s ratio) metamaterial which possesses excellent energy dissipation characteristics Following this, analytical modeling tools are employed to optimize the performance of the structures. during impact. In both cases, the mechanical response of the structures is evaluated experimentally. An optimized low thermal expansion structure can exhibit mechanical performance superior to that of Following this, analytical modeling tools are employed to optimize the performance of the structures. the bulk material. Additionally, an optimized auxetic lattice structure can theoretically absorb over 90% An optimized low thermal expansion structure can exhibit mechanical performance superior to that of of the energy of an impact. the bulk material. Additionally, an optimized auxetic lattice structure can theoretically absorb over 90% of the energy of an impact. Measur Crystal Alloy Using Nanoindentation Measur C. Tabata 1,2, T. Osada 1, T. Ohmura1, T. Yokokawa1, K. Kawagishi1 and S. Suzuki 2 Crystal Alloy Using Nanoindentation 1 Research Center for Structural Materials, National Institute for Materials Science (NIMS) 2 Department of Materials Science, Waseda UniversityC. Tabata 1,2, T. Osada 1, T. Ohmura1, T. Yokokawa1, K. Kawagishi1 and S. Suzuki 2 1 Research Center for Structural Materials, National Institute for Materials Science (NIMS) Ni-base single-crystal superalloys have excellent oxidation resistance at high temperatures. However, 2 Department of Materials Science, Waseda University impurity S are known to be detrimental especially for oxidation. This is most likely due to the decrease Ni-base single-crystal superalloys have excellent oxidation resistance at high temperatures. However, in the adhesion of the interface between the Al2O3 oxide layer and the Ni-base alloy by the segregation impurity S are known to be detrimental especially for oxidation. This is most likely due to the decrease of S. Yet, determining the differences in interfacial strength caused by S segregation has been difficult in the adhesion of the interface between the Al2O3 oxide layer and the Ni-base alloy by the segregation to do experimentally. The purpose of this research was to propose a mechanical test method that clarifies of S. Yet, determining the differences in interfacial strength caused by S segregation has been difficult the differences in interfacial strength between the Al2O3 oxide layer and the Ni-base alloy, depending on to do experimentally. The purpose of this research was to propose a mechanical test method that clarifies the S segregation level, using nanoindentation. Two types of Ni-9.8 wt.% Al alloys, alloy melted using the differences in interfacial strength between the Al2O3 oxide layer and the Ni-base alloy, depending on an Al2O3 crucible (high S) and alloy melted using a CaO crucible (low S) were prepared, and the S segregation level, using nanoindentation. Two types of Ni-9.8 wt.% Al alloys, alloy melted using nanoindentation was conducted using a diamond, 3-sided pyramid tip with the angle of 60 degrees. The an Al2O3 crucible (high S) and alloy melted using a CaO crucible (low S) were prepared, and initial indent position was at the Al2O3 oxide layer, 0.5 μm away from the interface, and the tests were conducted 17 times each, at 600 μN/s loading and unloading rate and 10 s holding time in between. The nanoindentation was conducted using a diamond, 3-sided pyramid tip with the angle of 60 degrees. The initial indent position was at the Al2O3 oxide layer, 0.5 μm away from the interface, and the tests were SEM images showed that the indentation moved towards the alloy during the test, helping initiate the conducted 17 times each, at 600 μN/s loading and unloading rate and 10 s holding time in between. The crack at the interface. Alloy (high S), which has higher S segregation level at the Al2O3/alloy interface, SEM images showed that the indentation moved towards the alloy during the test, helping initiate the showed that the first pop-in load was lower compared to alloy (low S). The Weibull distributions showed crack at the interface. Alloy (high S), which has higher S segregation level at the Al2O3/alloy interface, about 650 μN difference in the pop-in load due to the differences in S segregation level, and we were showed that the first pop-in load was lower compared to alloy (low S). The Weibull distributions showed successful in terms of quantitatively comparing the interfacial strength of the two specimens. about 650 μN difference in the pop-in load due to the differences in S segregation level, and we were successful in terms of quantitatively comparing the interfacial strength of the two specimens. ements of Interfacial Strength between Sulfur-segregated Al2O3 and Ni-Al Single ements of Interfacial Strength between Sulfur-segregated Al2O3 and Ni-Al Single Mechanical Response of Functional Lattice Structures Mechanical Response of Functional Lattice Structures M. Thielen3, J. Lee4 and D. S. Balint4 Poster Presentation ｜NIMS Award Symposium 2023 P3 ｜ EvaluationPP33--1111 PP33--1111 PP33--1122 PP33--1122 63
元のページ ../index.html#63