Development of Fatigue Simulation Method Considering the Microscopic Damage Mechanisms in CFRP and Prediction of Fatigue Life

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K20400
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0301:Mechanics of materials, production engineering, design engineering, fluid engineering, thermal engineering, mechanical dynamics, robotics, aerospace engineering, marine and maritime engineering, and related fields
• Research Institution: The University of Tokyo
• Principal Investigator: Aoki Ryoma 東京大学, 大学院工学系研究科(工学部), 助教 (60967868)
• Project Period (FY): 2022-08-31 – 2024-03-31
• Keywords: 炭素繊維強化複合材料 / 疲労負荷 / 微視的損傷進展 / 有限要素解析 / 残留強度評価

Outline of Final Research Achievements

This study aimed to evaluate the integrity of carbon fiber reinforced plastics (CFRP) during long-term operation by developing a fatigue damage model that considers microscopic damage. The cumulative mechanism of microscopic damage due to fatigue loading was clarified through numerical analysis, enabling the quantitative evaluation of microscopic damage up to the formation of cracks. Additionally, the analysis was extended to handle combined fatigue conditions with two different load levels. Furthermore, a method to predict the residual strength after fatigue was established as the durability evaluation. By comparing the predicted residual strength data with experimental data from several types of CFRP laminates, the accuracy of the predictions was validated, demonstrating the utility of the method in predicting the residual strength after fatigue.

Free Research Field

複合材料工学

Academic Significance and Societal Importance of the Research Achievements

CFRPの微視的損傷を考慮した疲労解析手法を開発し、巨視的なき裂形成に至るまでの損傷累積メカニズムを明らかにし、その損傷を定量的に評価することが可能となった。さらに、耐久性評価にとって重要な疲労後の残留強度を予測することも可能となった。これにより本手法は、航空機などの航空宇宙構造物だけでなく、近年注目を集める高圧水素タンクなどに対しても、耐久性評価を含めた設計支援技術として期待できる。