【公開日：2025.06.10】【最終更新日：2025.05.13】
課題データ / Project Data
課題番号 / Project Issue Number
24OS0041
利用課題名 / Title
Ni基合金のセル構造が有する水素トラップ能発現要因の解明
利用した実施機関 / Support Institute
大阪大学 / Osaka 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）マルチマテリアル化技術・次世代高分子マテリアル/Multi-material technologies / Next-generation high-molecular materials（副 / Sub）-
キーワード / Keywords
電子顕微鏡/ Electronic microscope
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)
Gokcekaya Ozkan
所属名 / Affiliation
大阪大学 工学研究科
共同利用者氏名 / Names of Collaborators Excluding Supporters in the Hub and Spoke Institutes
ARIM実施機関支援担当者 / Names of Supporters 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
OS-003：200kV原子分解能走査透過分析電子顕微鏡
OS-005：複合ビーム３次元加工・観察装置
報告書データ / Report
概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)
Recently, hydrogen energy has been attracting attention because it does not emit greenhouse gases. However, it has been reported that hydrogen penetrates metals in a hydrogen environment, resulting in hydrogen embrittlement (HE) that affects mechanical properties such as reduced ductility. In this study, hydrogen embrittlement behavior of Ni-based alloys fabricated by Powder bed fusion using a laser beam (PBF-LB) was investigated by thermal desorption spectroscopy (TDS) analyses and slow strain rate test (SSRT) performance. Various crystallographic textures were formed by controlling the PBF-LB scanning strategy. For each texture, ductility was reduced in the with-H environment compared to the without-H environment, but the rate of reduction in ductility was different. It exhibited that the microstructure control by PBF-LB suppressed HE of Ni-based alloy, thus, suggesting the advantage of PBF-LB to improve performance of metals in H environment via microstructure control.
実験 / Experimental
Specimens were prepared using PBF-LB by employing various patterns of scanning strategy. Microstructures were observed by scanning electron microscopy (SEM) and SEM-electron backscatter diffraction (SEM-EBSD). Hydrogen absorption volume in specimens was quantified by thermal desorption spectroscopy (TDS). A slow strain rate tensile test (SSRT) was performed under vacuum and hydrogen environment. The ratio of plastic strain under hydrogen environment to plastic strain under vacuum (Hydrogen Embrittlement Index: HEI) was used to evaluate HE susceptibility of HE. Detail microstructural analyses were carried out by FIB and HRTEM.
結果と考察 / Results and Discussion
This study presented HE behavior of specimens with different crystallographic textures and lattice defects by changing the scanning strategy of PBF-LB/M. Hydrogen absorption volume was not significantly varied among the specimens. Interestingly, HEI showed obvious changes in accordance with the conditions of microstructure and lattice defect, which were related to the crystallographic texture. Furthermore, a relationship between the PBF-LB/M-specific solidification structure and hydrogen embrittlement behavior was observed.
図・表・数式 / Figures, Tables and Equations
Fig. 1
Fig. 2
その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)
O. Gokcekaya, T. Ishimoto, S. Hibino, J. Yasutomi, T. Narushima, T. Nakano, Acta Materialia, 212, (2021), 116876.
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)
口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.
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