Creation of phase-transforming cellular lattice by multi-material metal-additive manufacturing - Pioneering 4D printing

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K22063
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 26:Materials engineering and related fields
• Research Institution: Osaka University
• Principal Investigator: KOIZUMI Yuichiro 大阪大学, 工学研究科, 教授 (10322174)
• Project Period (FY): 2019-06-28 – 2022-03-31
• Keywords: Additive Manufacturing / 4Dプリント / 合金化 / 相転移 / 結晶構造 / 双安定性 / 異種金属 / 形状記憶

Outline of Final Research Achievements

A series of studies have been conducted to pioneer 4D printing by creating phase-transforming lattice structures, a.k.a. phase transforming cellular material (PXCM), using multi metal-additive manufacturing; electron beam irradiation experiments were conducted as a preliminary step to the powder-bed fusion (PBF) of Ti alloy/Cu composites; and, for 4D printing, a fundamental study of the elemental structure and elastic properties of PXCM fabricated by powder-bed fusion of elastomers was developed for future applications to metals. In addition, we have fabricated thermally induced PXCM and investigated their behavior of the bimetal-incorporated lattice structure as a function of temperature change, showed that the phase transformation could be induced by heating and cooling, and extracted the issues to be solved on a larger scale. We also studied the design method for conformalization for unit cell design according to the external shape of the modeled object.

Free Research Field

材料工学

Academic Significance and Societal Importance of the Research Achievements

多色刷り金属AMの基礎として、複材粉末床の選択的溶融の基礎研究を行い、異材粉末床の境界領域の溶融における課題を示した。また将来重要となる混合粉末の分離回収法として振動分離の可能性を示し、実際に簡便に分離できる条件を見出した。また、相転移するラティスの4Dプリントの基礎となる、構造と特性の関係のデータ科学的手法を構築した。さらに、バイメタルを組み込んだラティス構造の温度変化による相転移挙動の研究を発展させた。本研究の成果は、多色刷り金属AMが高精度化した際に必要となる相転移するラティスの創成による4Dプリントの学術的基礎となり、新規メタ材料創成のための方向性を示す研究としての社会的意義がある。