Study on creep properties of nano-materials by using specimens with controlled shape, or stress concentration, and in situ observation

2016 Fiscal Year Final Research Report

• Project/Area Number: 26289007
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Materials/Mechanics of materials
• Research Institution: Osaka University
• Principal Investigator: Hirakata Hiroyuki 大阪大学, 工学(系)研究科(研究院), 准教授 (40362454)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: マイクロ・ナノ材料力学 / ナノ構造 / クリープ / 材料強度

Outline of Final Research Achievements

Creep experiments were conducted for doglegged nanocolumns with controlled stress concentrated sites, which included the corner of the doglegged shape and the column/substrate interface. Ti and Ta2O5 nanocolumns deformed in a time-dependent manner under room temperature and then fractured at the stress concentrated sites. Stress analyses considering the creep of the nanocolumns suggested that the nanoscale stress concentration dominated the creep fracture life. In addition, the creep rate in air environment was much higher than that in vacuum environment. The results indicated that the creep deformation in the nanocolumns was significantly accelerated by air or moisture environment.

Free Research Field

機械材料・材料力学