【公開日：2024.07.25】【最終更新日：2024.06.22】

課題データ / Project Data

課題番号 / Project Issue Number

23NU0042

利用課題名 / Title

金属３Ｄプリンタ造形体の材料組織観察と構造解析

利用した実施機関 / Support Institute

名古屋大学 / Nagoya Univ.

機関外・機関内の利用 / External or Internal Use

内部利用（ARIM事業参画者以外）/Internal Use (by non ARIM members)

技術領域 / Technology Area

【横断技術領域 / Cross-Technology Area】（主 / Main）計測・分析/Advanced Characterization（副 / Sub）-

【重要技術領域 / Important Technology Area】（主 / Main）量子・電子制御により革新的な機能を発現するマテリアル/Materials using quantum and electronic control to perform innovative functions（副 / Sub）-

キーワード / Keywords

3Dプリンタ，金属積層造形，レーザ粉末床溶融結合法，アルミニウム合金,電子顕微鏡/ Electronic microscope,表面・界面・粒界制御/ Surface/interface/grain boundary control

利用者と利用形態 / User and Support Type

利用者名（課題申請者）/ User Name (Project Applicant)

高田 尚記

所属名 / Affiliation

名古屋大学大学院工学研究科

共同利用者氏名 / Names of Collaborators in Other Institutes Than Hub and Spoke Institutes

王文苑,大谷祐貴,キム ダソム,小橋眞

ARIM実施機関支援担当者 / Names of Collaborators in The Hub and Spoke Institutes

利用形態 / Support Type

（主 / Main）機器利用/Equipment Utilization（副 / Sub）-

利用した主な設備 / Equipment Used in This Project

NU-103：高分解能透過電子顕微鏡システム

報告書データ / Report

概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)

　Laser powder bed fusion (L-PBF), referred to as one of the representative metal additive manufacturing processes, is a promising route to fabricate complex-shaped Al alloy components with unique microstructures. It has been reported that the L-PBF built Al–2.5Fe (mass%) binary alloy exhibits a high tensile strength of approximately 300 MPa due to finely dispersed Al₆Fe metastable phases. However, the metastable Al₆Fe phase could transform into the stable Al₁₃Fe₄ phase after long-term exposure at elevated temperatures, resulting in reduced strength. Therefore, it is necessary to stabilize the fine metastable Al₆Fe phase for further strengthening at elevated temperatures. In this study, we have selected Mn and/or Cu as a third alloy element for stabilizing the Al₆Fe phase in terms of Al–Fe–Mn and Al–Fe–Cu ternary phase diagrams and made an attempt at L-PBF processing using the ternary alloy powders. Microstructural characterizations were performed by transmission electron microscopy (TEM).

実験 / Experimental

　The Al–2.5Fe–2Mn and Al–2.5Fe–2Cu (mass%) ternary alloy powders with a mean particle size of approximately 20 μm, were produced by gas atomization. The L-PBF process was performed using a 3D system ProX 200 equipped with a Yb-fiber laser. These alloy samples were manufactured under a wide range of laser scan speeds (0.6 ~ 1.4 m/s) and laser power (102 ~ 204 W) for optimization of processing parameters for densification. The applied other process parameters were as follows: beam spot size ~100 μm, hatch distance = 100 μm, and bedded-powder layer thickness = 30 μm. The hexagonal grid laser scanning pattern was applied to manufacture the alloy samples. TEM observations were performed using JEOL JEM-2100F/HK.

結果と考察 / Results and Discussion

　The optimized laser parameters for each alloy powder enabled the manufacturing of dense samples with a relative density above 99 %. An OM image showing the microstructure of the Al–2.5Fe–2Mn alloy sample is presented in Fig. 1(a). The observed section is parallel to the building (z) direction. The characteristic melt-pool structure is comprised of a number of half-cylindrical melt pools (corresponding to the locally melted and rapidly solidified regions). As shown in the TEM images (Fig. 1 (b, c)), relatively large-sized Al₆(Fe, Mn) phases with a cellular morphology (dark contrast) appeared localized along melt-pool boundaries, whereas much finer nanoscale particles of the Al₆(Fe, Mn) phase (dark contrast) were homogeneously dispersed in the α-Al matrix inside the melt pools.

図・表・数式 / Figures, Tables and Equations

Fig. 1. (a) Optical micrograph showing the microstructure of L-PBF built Al–2.5Fe–2Mn alloy sample. TEM bright-field images showing the microstructures of (b) the melt pool boundary and (c) inside the melt pool.

その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)

　The technical support of TEM operations by K. Higuchi and Y. Yamamoto was gratefully acknowledged.

成果発表・成果利用 / Publication and Patents

論文・プロシーディング（DOIのあるもの） / DOI (Publication and Proceedings)

1. Wenyuan Wang, Design of Al–Fe–Mn alloy for both high-temperature strength and sufficient processability of laser powder bed fusion, Additive Manufacturing, 68, 103524(2023).
   DOI: https://doi.org/10.1016/j.addma.2023.103524
   
2. Yuki Otani, CALPHAD-aided design of high-strength Al-Si-Mg alloys for sufficient laser powder bed fusion processability, Journal of Alloys and Compounds, 977, 173449(2024).
   DOI: https://doi.org/10.1016/j.jallcom.2024.173449
   
3. Ruoqi Li, Controlling the addition of solute Ti in Al-Mg-Zn-Cu-Ni alloy for enhanced high-temperature creep properties, Materials Science and Engineering: A, 889, 145859(2024).
   DOI: https://doi.org/10.1016/j.msea.2023.145859
   

口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.

1. Y. Otani, K. Saki, N. Takata, A. Suzuki, M. Kobashi, M. Kato, "Processability and solidification microstructure of Al-10Si-4.5Mg alloy fabricated by laser powder bed fusion" International Conference on PROCESSING & MANUFACTURING OF ADVANCED MATERIALS, Processing, Fabrication, Properties, Applications: Thermec'2023 （Vienna, Austria），2023年7月6日.
2. W. Wang, N. Takata, A. Suzuki, M. Kobashi, M. Kato, "Design of high-temperature Al–Fe based alloys feasible for laser powder bed fusion process" International Conference on PROCESSING & MANUFACTURING OF ADVANCED MATERIALS, Processing, Fabrication, Properties, Applications: Thermec'2023 （Vienna, Austria），2023年7月6日.
3. Naoki Takata, Takanobu Miyawaki, Yue Cheng, Asuka Suzuki, Makoto Kobashi, Masaki Kato, "Controlling solidification microstructure of aluminum alloys using eutectic/peritectic reactions in laser powder bed fusion process", 2023 MRS fall meeting & Exhibit（Boston, USA），2023年11月30日.

特許 / Patents

特許出願件数 / Number of Patent Applications：0件
特許登録件数 / Number of Registered Patents：0件