耐疲労スマートペーストをボルト穴に適用した場合の疲労き裂進展の自動抑制および目視検出  [in Japanese] Automatic Restraint and Visual Detection of Fatigue Crack Growth When Applying an Anti-fatigue Smart Paste to Bolt Holes  [in Japanese]

An anti-fatigue smart paste, which consists of fine alumina particles and silicone grease with low viscosity, was applied to a bolt hole (and its periphery in some cases) in a steel plate specimen, and the effects of the smart paste on automatic restraint and visual detection of fatigue crack growth were experimentally investigated through fatigue tests. Fractographic observations using a SEM (Scanning Electron Microscope) were also carried out. As a result, approximately 20∼410% increase in failure life was produced by the wedge effect of the alumina particles in the smart paste. When the smart paste was applied, remarkable black color developed in the white paste along the paths of crack growth, exceedingly facilitating the visual detection of the crack growth.