金属 Additive Manufacturing による形状・材質同時制御と異方性高機能化

中野 貴由（なかの たかよし） 氏
大阪大学大学院工学研究科マテリアル生産科学専攻
大阪大学工学研究科附属3DPTec統合センター

金属Additive Manufacturing（AM）は、デジタル時代における先進的製造プロセスの主軸をなし、個別のカスタム設計や多品種生産を具現化する革新的技術である。とりわけ金属を直接溶融・凝固させるAM手法は、局所的な超急冷凝固プロセスを制御することで、従来の機械加工では不可能な複雑三次元形状の創成と、原子レベルの結晶配向制御に基づく材質制御の同時達成を可能とする。その結果、等方性／異方性を自在に操る「形状・材質同時制御」が実現し、造形物の劇的な高機能化と高付加価値化がもたらされる。

本技術は、航空宇宙、医療、エネルギー、モビリティなど、高度な信頼性が要求される基盤分野の次世代イノベーションを牽引する。大阪大学では、2014年に国内初のAMセンターを立ち上げ、2026年4月には「3DPTec統合センター」へと発展改組した。現在はデジタルツイン技術を駆使し、金属、セラミックス、樹脂、さらにはバイオ材料までを網羅する最先端AM拠点として研究を深化させている。 本講演では、結晶対称性や優先成長方位の制御による特定部位への結晶配向付与や階層的組織制御、さらには多変数トポロジー最適化などを概説し、金属材料の異方性を人為的に操る高機能化戦略の最前線を紹介する。

研究・管理棟（A棟）2階 会議場（1236，1237室）， zoom

The Last Mile of discovery: Why communication decides what science becomes

Dr. Arnaud Stiepen
Nexus by Arnaud Stiepen

We often treat communication as what happens after the science is done: the press release, the outreach event, the final slide. I want to argue the opposite. In the era of big, international space science, communication is not the last, optional step of discovery but the infrastructure that makes discovery matter, and often the infrastructure that makes it possible at all. A mission today is a conversation among hundreds of engineers and scientists across continents, languages and institutions; it survives on how well they understand one another. It is funded by publics who will never read a paper, but who decide, through the stories they are told, whether a journey to an asteroid or a distant planet is worth their trust. And it endures across borders because science remains one of the few languages nations still share. Having spent years inside international collaborations on NASA and European missions, then a decade devoted to making science understood, I have come to see communication as the hardest and most underestimated problem in research, harder, often, than the physics itself. Drawing on examples from NASA, ESA and the private sector, this talk asks what we lose when science is not communicated, what we gain when it is, and why the ability to turn data into meaning may be one of the most important skills a scientist never trained for.

Conference Hall (2nd floor/ Research and Administration Building A),　Via Zoom

The status and science of the Proba-3 mission

Dr. Stanislav Gunar
Astronomical Institute of the Czech Academy of Sciences

The giant distributed coronagraph ASPIICS onboard the formation-flying mission PROBA-3 of ESA investigates the hitherto practically unexplored inner depths of the solar corona. This region lies above the reach of disk imagers such as SDO/AIA and below the inner limit of other space coronagraphs. Although difficult to observe, the inner corona is a place of great interest. This is where the fast solar wind gets accelerated to supersonic velocities and where CMEs also reach their maximum accelerations. It is also the place where the transition between the regions of the closed and open magnetic field often happens and the slow solar wind originates.

We will present the current status and the most recent scientific results obtained by the Proba-3 mission. We will also look at the unique concept of the formation-flying technology that is the focus of the PROBA-3 mission and the workings of ASPIICS, and discuss which scientific fields are benefiting from its capabilities. For example, thanks to its field of view reaching from 1.098 to 3 Rsun, good spatial resolution and minimized straylight, ASPIICS is able to follow the connectivity of magnetic structures in the corona down to the solar surface. When coupled with regular long duration (up to 6 hours) observations, it allows us to compare and validate the MHD models of the large-scale coronal magnetic field configuration and its evolution. The inner field-of-view limit reaching very close to the solar surface also enables us to study the onset and early evolution of CMEs or to follow erupting prominences beyond the reaches of the disk imagers.

Conference Room A (1257) (2nd floor/ New Building A),　Via Zoom

Emerging boundaries in the planet formation process

Dr. Erik Petigura
University of California, Los Angeles

The eight planets in the solar system fall neatly into three main categories: rocky terrestrials, hydrogen-dominated Jovians, and ice giants. These planet classes reflect different formation environments, processes, and timescales. Extrasolar planets, in contrast, span a continuum of sizes, masses, and orbit. They demand a richer taxonomy. Recently, large, multivariate studies of transiting exoplanets have revealed new dividing lines in the planet formation process. Transitions in the occurrence, eccentricity, and host star metallicity distributions have shown that close-in planets larger than Neptune form according to very different pathways compared to their smaller counterparts. At the same time, new synergies involving RVs, direct imaging, and astrometry are beginning to illuminate the boundaries between the most massive planets (formed by core accretion) and the least massive brown dwarfs (formed by direct collapse). Surprisingly, this empirical boundary occurs well below the deuterium burning limit. Studies like this offer a preview of the types of insights we can look forward to with the upcoming release of Gaia DR4 in December of this year, which will dramatically expand our census of giant planets and brown dwarfs.

Conference Hall (2nd floor/ Research and Administration Building A),　Via Zoom

The centre of the Milky Way

Dr. Mattia Sormani
University of Insubria (Como, Italy)

I will give an introduction to the structure and dynamics of the central 3 kpc of the Milky Way. The Galactic bar efficiently drives gas from the Galactic disc towards the centre at a rate of ~0.8 Msun/yr, creating a ring-like accumulation of molecular gas at a radius of R=120pc known as the Central Molecular Zone (CMZ). The CMZ is the Milky Way analogue of the star-forming nuclear rings commonly observed at the centre of external barred galaxies, and its formation is governed by a dynamical process similar to that responsible for creating gaps in Saturn's rings. Once in the CMZ ring, approximately 10% of the gas is converted into stars by intense star formation activity. Over Gyr timescales, this activity builds up a flattened stellar system known as the nuclear stellar disc (NSD), which currently has a mass of 10^9 Msun and dominates the gravitational potential of the Milky Way at 30pc<R<300pc. Most of the remaining gas is ejected perpendicularly to the plane by a Galactic outflow powered either by stellar feedback and/or AGN activity. A small fraction continues moving radially inwards, feeding the circum-nuclear disc (CND) at radii of few pc and contributing to the in-situ growth of the nuclear star cluster (NSC). Only a tiny fraction eventually enters the sphere of influence of the central black hole SgrA* at R<1pc.

Conference Hall (2nd floor/ Research and Administration Building A),　Via Zoom