Porous materials such as polymeric foam are widely adopted in engineering and biomedical fields. Porous materials often exhibit complex nonlinear behaviors and are sensitive to material and environmental factors including cell size and shape, amount of porosity, and temperature, which are influenced by the type of base materials, reinforcements, method of fabrication, etc. Hence, the material characteristics of porous materials such as compressive stress-strain behavior and void volume fraction according to aforementioned factors should be precisely identified. In this study, unconfined uniaxial compressive test for two types of closed-cell structure polyurethane foam, namely, 0.16 and 0.32 g/cm3 of densities were carried out. In addition, the void volume fraction of three different domains, namely, center, surface and buckling regions under various compressive strains (10%, 30 %, 50 % and 70 %) were quantitatively observed using Micro 3D Computed Tomography(micro-CT) scanning system. Based on the experimental results, the relationship between compressive strain and void volume fraction with respect to cell size, density and boundary condition were investigated.

1. 서 론
 2. 실험 방법
  2.1 Polyurethane foam sample preparations
  2.2 Mechanical testing and analysis
 3. 결과 및 고찰
 4. 결 론
 Acknowledgement
 Reference

• 이은선(부산대학교병원 의생명연구원) | Eun Sun Lee (Biomedical Research Institute, Pusan National University Hospital)
• 고태식(부산대학교병원 정형외과) | Tae Sik Goh (Department of Orthopaedic Surgery and Biomedical Research Institute, Pusan National University Hospital)
• 이치승(부산대학교병원 의생명연구원, 부산대학교 의과대학) | Chi-Seung Lee (Biomedical Research Institute, Pusan National University Hospital, School of Medicine, Pusan National University) Corresponding author