T형 미소 인장 시편의 좌굴 회피 최적 설계

Microscale structures such as thin films exhibit mechanical properties distinct from those of macroscale counterparts, necessitating accurate characterization of material properties at the microscale level. T-shaped micro-tensile specimens are widely used for this purpose; however, specimen geometry has not been systematically investigated, leading to stress concentration at the fillet region and buckling at the specimen head, which ultimately compromises measurement accuracy. To address these issues, the present study proposes an optimized specimen geometry that minimizes stress concentration and prevents head buckling. Finite element analysis and surrogate model-based optimization were employed to analyze stress and buckling behavior under various design parameters. The resulting design is expected to serve as a reference for the future development of thin-film tensile specimens.