Watanabe Watanabe MM 18NIMS Talk NA-3 NIMS Talk NA-3 Understanding Process-Structure-Property Linkage of Understanding Process-Structure-Property Linkage of Field Director, Research Center for Structural Materials (RCSM), Field Director, Research Center for Structural Materials (RCSM), Abstract Abstract Metal additive manufacturing (AM) has attracted a lot of interest as a new processing technique to Metal additive manufacturing (AM) has attracted a lot of interest as a new processing technique to realize complex geometries based on a computer-aided design (CAD). Laser Powder Bed Fusion realize complex geometries based on a computer-aided design (CAD). Laser Powder Bed Fusion (LPBF) is the most widely used powder bed metal AM process in the industry. In LPBF, it is important (LPBF) is the most widely used powder bed metal AM process in the industry. In LPBF, it is important to suppress the formation of defects such as cracks and pores through rapid heating and cooling by a to suppress the formation of defects such as cracks and pores through rapid heating and cooling by a laser beam. In addition, since a characteristic anisotropic microstructure is formed, it is necessary to laser beam. In addition, since a characteristic anisotropic microstructure is formed, it is necessary to understand the process-microstructure-property correlation and establish microstructure control understand the process-microstructure-property correlation and establish microstructure control techniques to achieve the required mechanical properties. The geometry of a component has a large techniques to achieve the required mechanical properties. The geometry of a component has a large influence on the temperature field during the process, and so the microstructure can vary greatly influence on the temperature field during the process, and so the microstructure can vary greatly depending on the position even under the same laser conditions. Therefore, in the development of new depending on the position even under the same laser conditions. Therefore, in the development of new components, optimization by trial and error using only experiments is extremely inefficient, and the components, optimization by trial and error using only experiments is extremely inefficient, and the establishment of prediction techniques using computation is essential. We have studied heat-resistant establishment of prediction techniques using computation is essential. We have studied heat-resistant alloys with the aim of accumulating process-microstructure-property correlation data in the LPBF alloys with the aim of accumulating process-microstructure-property correlation data in the LPBF process and establishing our own prediction technique. process and establishing our own prediction technique. The solidification microstructure and cracking behavior of the LPBF Ni-based alloys were The solidification microstructure and cracking behavior of the LPBF Ni-based alloys were investigated by controlling the temperature field through the constricted sample geometry [1]. In-situ investigated by controlling the temperature field through the constricted sample geometry [1]. In-situ temperature monitoring, part-scale and multi-track thermal analyses were performed. The correlations temperature monitoring, part-scale and multi-track thermal analyses were performed. The correlations between the temperature gradient and solidification rate and the microstructures were quantitatively between the temperature gradient and solidification rate and the microstructures were quantitatively revealed. Microstructure control by a different type of a laser profile was investigated for pure Ni by revealed. Microstructure control by a different type of a laser profile was investigated for pure Ni by inducing a planar melt pool with a flat-top laser [2]. The optimized process conditions succeeded to inducing a planar melt pool with a flat-top laser [2]. The optimized process conditions succeeded to form a single crystal structure with a homogeneous near-{001}<100> texture and suppressed high-form a single crystal structure with a homogeneous near-{001}<100> texture and suppressed high-angle grain boundary. The melt pool morphology significantly affected solidification microstructure. angle grain boundary. The melt pool morphology significantly affected solidification microstructure. The CFD simulation of melting behavior was developed to predict melt pool dimensions and gas pore The CFD simulation of melting behavior was developed to predict melt pool dimensions and gas pore formation [3]. Moreover, by developing in-house programs of Lattice Boltzmann method coupled with formation [3]. Moreover, by developing in-house programs of Lattice Boltzmann method coupled with multiphase field method, the solidification microstructure was successfully predicted by considering multiphase field method, the solidification microstructure was successfully predicted by considering the melt pool flow and grain anisotropy. Other research activities to understand and predict the process-the melt pool flow and grain anisotropy. Other research activities to understand and predict the process-structure-property linkage of LPBF will be introduced in the presentation. structure-property linkage of LPBF will be introduced in the presentation. [1] M. Kusano, M. [1] M. Kusano, M. [2] D.E. Jodi, T. Kitashima, Y. Koizumi, T. Nakano, M. [2] D.E. Jodi, T. Kitashima, Y. Koizumi, T. Nakano, M. [3] J. Katagiri, M. Kusano, S. Nomoto, [3] J. Katagiri, M. Kusano, S. Nomoto, Watanabe, Materials & Design, 222Watanabe, Materials & Design, 222Watanabe, Case Studies in Thermal Engineering, 50 (2023) 103477. Watanabe, Case Studies in Thermal Engineering, 50 (2023) 103477. M. M. Makoto Watanabe is the Director of the Materials Manufacturing Field, Research Center for Structural Makoto Watanabe is the Director of the Materials Manufacturing Field, Research Center for Structural Materials, National Institute for Materials Science (NIMS), Japan. He is also Group Leader of the Materials, National Institute for Materials Science (NIMS), Japan. He is also Group Leader of the Additive Manufacturing Group in the same field. He received his Ph.D. from the Department of Additive Manufacturing Group in the same field. He received his Ph.D. from the Department of Materials Engineering at the University of Tokyo in 2000. He worked at Princeton University Materials Engineering at the University of Tokyo in 2000. He worked at Princeton University (Postdoctoral Researcher (2000-2002)) and at the University of California Santa Barbara (Research (Postdoctoral Researcher (2000-2002)) and at the University of California Santa Barbara (Research Associate (2002-2004)), and then joined the Thermal Spray Coatings Group at NIMS in 2004. He also Associate (2002-2004)), and then joined the Thermal Spray Coatings Group at NIMS in 2004. He also stayed at Stanford University as a visiting researcher (2011-2013), and worked at the University of stayed at Stanford University as a visiting researcher (2011-2013), and worked at the University of Tokyo as an associate professor under the cross-appointment system (2017-2020). Recently, he has Tokyo as an associate professor under the cross-appointment system (2017-2020). Recently, he has mainly studied about additive manufacturing (AM) of high temperature alloys by combining mainly studied about additive manufacturing (AM) of high temperature alloys by combining experimental and computational approaches to develop new alloys suitable for AM. experimental and computational approaches to develop new alloys suitable for AM. NIMS Award Symposium 2023National Institute for Materials Science (NIMS) National Institute for Materials Science (NIMS) Additive Additive NIMS Award Session (2022) 111016. (2022) 111016. Watanabe, Additive Manufacturing Letters, 3 (2022) 100066. Watanabe, Additive Manufacturing Letters, 3 (2022) 100066. akoto akoto Manufacturing Manufacturing
元のページ ../index.html#18