Proposing of damage assessment method of seismic-loaded structural material based on surface roughness measurement

2015 Fiscal Year Final Research Report

• Project/Area Number: 26889001
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Materials/Mechanics of materials
• Research Institution: Hokkaido University
• Principal Investigator: FUJIMURA NAO 北海道大学, 工学(系)研究科(研究院), 助教 (40732988)
• Project Period (FY): 2014-08-29 – 2016-03-31
• Keywords: 疲労損傷評価 / 表面粗さ / ステンレス鋼

Outline of Final Research Achievements

In order to evaluate seismic-loaded damage based on the changes in surface roughness of material due to cyclic deformation, the effects of strain rate on the fatigue life and the changes in surface roughness of austenitic stainless steel was investigated. Low cycle fatigue tests were conducted under strain rate: 4%/sec, and the fatigue lives were compared with the fatigue lives obtained under 0.4%/sec. As a result, the fatigue lives at 4%/sec and 0.4%/sec were nearly equal. This shows that the tenfold increase in strain rate do not affect low cycle fatigue life. During the fatigue tests, specimen’s surface roughness was regularly measured using a laser scanning microscope. Surface roughness measurement showed that the changes in surface roughness at 4%/sec were little different from that at 0.4%/sec. Based on these results, the damage assessment method on the basis of surface roughness was discussed.

Free Research Field

工学