OS1106 Strength evaluation of titanium nanocolumns by controlling nanoscale shape, or stress field
Details
To clarify whether the nanoscale stress concentration dominated the fracture, we created titanium doglegged nanocolumns on a titanium thin film using dynamic oblique deposition. Two types of specimens were prepared: a forward specimen (loading to dogleg opening direction) and a reverse specimen (loading to dogleg closing direction). Nanoscale tensile stress concentration occurred at the dogleg corner of column in the reverse specimen, whereas it occurred at the corner of column root in the forward specimen. The reverse specimen has a greater stress gradient than the forward specimen. Fracture experiments using micro-brick specimens revealed that the fracture occurred at the nanoscale stress concentration sites in both specimens, suggesting that the nanoscale stress concentration has an impact on the fracture. Loading-unloading experiments indicated that no partial fracture occurred up to almost the fracture load. Dominant mechanics of the fracture was discussed on the basis of the results.
