Development of plastic deformarable hard material and investigation of deformation mechanism

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K04671
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 26030:Composite materials and interfaces-related
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Nakayama Hiroyuki 国立研究開発法人産業技術総合研究所, 材料・化学領域, 主任研究員 (00510075)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: マルテンサイト / 超硬合金 / サーメット

Outline of Final Research Achievements

A (Fe-Ni) alloy, exhibiting stress induced phase transformation, was used as a binder phase in cemented carbides (WC-20 mass% (Fe-Ni)) and thermets (TiC-25 mass% (Fe-Ni)). The fraction of fcc phase in (Fe-Ni) binder phase was increased with increasing Ni content. The strength and deformation behavior of these materials were investigated. As a result, strength and elongation were improved at the appropriate Ni composition. The XRD pattern obtained from the fracture surface of the sample cleared that the fcc phase in (Fe-Ni) binder phase transformed to bcc phase by applied stress. The stress induced phase transformation can realize the contradict properties of strength and elongation in the materials.

Free Research Field

粉末冶金

Academic Significance and Societal Importance of the Research Achievements

硬質材料は切削工具や金型などに用いられている。これらの材料は高速切削やプレス成型のような過酷な使用環境下で用いられることが多い。そのため、強度や硬度といった特性に加えて、相反する延性や靭性も必要となる。
本研究成果は、硬質材料の強度や硬度を低下させることなく延性や靭性を向上させることが可能となり、より過酷な使用条件下での利用が可能となる。