Development of Multiaxial Creep Life Evaluation Method with Small Size Specimen for Thermal Power Plant Designing

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K05973
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Materials/Mechanics of materials
• Research Institution: University of Fukui
• Principal Investigator: Hiyoshi Noritake 福井大学, 学術研究院工学系部門, 准教授 (30342489)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 多軸 / クリープ / 寿命評価 / 実験力学

Outline of Final Research Achievements

A creep damage evaluation under multiaxial stress conditions is required to ensure the integrity of high-temperature structural components such as boiler pipes of thermal power plants and turbine blades of aircraft engines.
In order to solve these issues, a new method of high-temperature multiaxial creep experiments is established in this work.
Particularly in the field of material evaluation and testing, we challenged the use of small size specimens because the miniaturization of the material size to be evaluated is effective in improving its accuracy. A cruciform specimen, which has 50 mm x 50 mm size was designed, and a testing system was developed for this specimen to establish a high-temperature multiaxial creep testing. A major feature of this system is that the deformation and strain of a specimen in a high-temperature electric furnace can be measured by a non-contact investigation system using an optical camera.

Free Research Field

材料強度

Academic Significance and Societal Importance of the Research Achievements

電気の安定供給には火力発電の効果的な併用が不可欠である。また，航空需要の増大に伴い航空機の安全保障も不可欠である。すべての高温産業機器は，高温環境のためにクリープ現象によって材料変形を生じる。本研究課題では実機材料のクリープ損傷の程度を実験検証で高精度に評価できる手法を開発した。
また，電気炉内の材料の変形をその場観察する技術も開発し，これまで未解明だった高温中での金属変形を明らかにした。