Frontiers in Solidification Science VIII: Poster Session
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Chemistry and Physics of Materials Committee, TMS: Phase Transformations Committee, TMS: Solidification Committee, TMS: Computational Materials Science and Engineering Committee
Program Organizers: Damien Tourret, IMDEA Materials Institute; Amy Clarke, Los Alamos National Laboratory; Ulrike Hecht, Access e.V.; Nana Ofori-Opoku, Canadian Nuclear Laboratories; Melis Serefoglu, Marmara University; Tiberiu Stan, Asml
Tuesday 5:30 PM
March 16, 2021
Room: RM 56
Location: TMS2021 Virtual
Session Chair: Amy Clarke, Colorado School of Mines; Ulrike Hecht, Access e.V.; Nana Ofori-Opoku, Canadian Nuclear Laboratories; Melis Şerefoğlu, Koç University; Tiberiu Stan, Northwestern University; Damien Tourret, IMDEA Materials
Data-assimilation for Dendritic Solidification Using Phase-field Simulation Based on Limited Observation Data: Yuki Imai1; Shinji Sakane1; Tomohiro Takaki1; 1Kyoto Institute of Techonology
The details of dendrite growth in alloy solidification have been becoming clear due to the recent development of experimental and numerical techniques. Nevertheless, crucial problems are remaining in both experiment and simulation, such as low resolution in experiments and lack of material parameters in simulations. Thus, a new technology combining the cutting-edge techniques in experiment and simulation is required. Recently, the data-assimilation was applied to obtain the interfacial properties [Phys. Rev. E, 101 (2020) 052121]. Although it is the promising approach, the solidification microstructures obtained in experiment are often not perfect even using the state-of-the-art technology. In this study, we investigate the data-assimilation based on such limited observation data. Here, the phase-field method is employed as a material microstructure evaluation model.
Electronic-structure Calculations of Local Orders in Liquid Metals: Byeongchan Lee1; Geun Woo Lee2; 1Kyung Hee University; 2Korea Research Institute of Science and Standards
Local orders in liquid metals are critical in various transitions, including a liquid-solid transition or solidification as witnessed in the depth of undercooling, and first principles calculations are playing a pivotal role with access to detailed local structures. Here we present first principles calculations in liquid Ti, Mo and Ni as representative materials of early, mid, and late transition metals respectively. First of all, the change in local orders is discussed as a function of temperature or pressure, and the results are compared against one another. Second, thermophysical properties such as viscosity are discussed and compared. Last, we try to suggest the origin of the differences in material properties with detailed electronic-structure calculations. Specifically, the bond order and the hybridization index are explained, and connected to the formation and changes of local orders. We further discuss the influence of local orders on the solidification process.
Multi-phase-field Lattice Boltzmann Modeling and Simulations for Semi-solid Deformation: Namito Yamanaka1; Shinji Sakane1; Tomohiro Takaki1; 1Kyoto Institute of Technology
In casting processes, the semi-solid deformation causes macrosegregation. To reduce the macrosegregation, it is crucial to elucidate the mechanisms of semi-solid deformation. Thus, modeling and simulation studies are indispensable for a better understanding of the semi-solid deformation. However, the semi-solid deformation is a very complicated multi physics problem including solidification, liquid flow, solid motion, solid-solid interaction, and so on. In our previous study, we constructed the multi-phase-field lattice Boltzmann (MPF-LB) model, which can simulate the growth of multiple dendrites with motion, liquid flow, collision, and coalescence and subsequent grain growth, to express the formation process of equiaxed solidification structures [Comput. Mater. Sci., 147 (2018) 124–131]. In this study, the MPF-LB model is modified to enable the accurate simulation of the semi-solid deformation. Also, shear deformations of granular materials are simulated by systematically changing the solid fraction and grain morphology, and the mechanisms in semi-solid deformation are discussed in detail.