Achievement of high toughened metallic glass with single amorphous phase through designing of anisotropy of random structure

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K04899
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 30010:Crystal engineering-related
• Research Institution: Tohoku University
• Principal Investigator: Yamada Rui 東北大学, 金属材料研究所, 助教 (40706892)
• Co-Investigator(Kenkyū-buntansha): 才田 淳治 東北大学, 学際科学フロンティア研究所, 教授 (20359540)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 金属ガラス / ガラス状態傾斜 / 高靭性化

Outline of Final Research Achievements

In the present study, we attempted to improve the brittleness of metallic glass through thermally introduced anisotropy of random structure and glassy state gradient in a monolithic metallic glass.
We developed a rapid cooling machine and jigs that can hold the sample in various directions. After heating a Zr50Cu40Al10 metallic glass rod sample to the supercooled liquid region, we selectively cooled one part of the sample by attaching a copper mesh stage which was indirectly cooled with liquid nitrogen. To do so, we successfully introduced a glassy state gradient through the process. The compression test results showed that a slight plasticity was observed just before the final fracture in the sample. From the fracture surface observation and DIC analysis results, it was considered that the appearance of plasticity was caused by the deflection of the crack propagation along the glassy state gradient during fracture.

Free Research Field

非晶質材料、金属ガラス

Academic Significance and Societal Importance of the Research Achievements

本研究はランダム構造の異方性という新しい概念に基づいてアモルファス相単相での脆性改善を試みたものであり、実際に提案する熱的手法を通じて1試料内にガラス状態傾斜を形成することに成功した。またそれを通じて亀裂の進展を制御できる可能性を示しかつそれによって脆性特性が改善され得ることを明らかにすることができた。このことは今後非晶質材料全般の強度設計に新たな指針を提示するとともに、これまで主に結晶材料の範疇で議論されてきた傾斜機能材料への非晶質材料の新たな展開も今後大いに期待される。