The Effect of Pore Size on Thermal Stress Distribution in Metal Porous Structures

This study examines the structural characteristics of porous materials derived from scanning electron microscopy (SEM) images of bamboo biochar. The goal is to design a metal-porous structure using biomimicry. The stress distribution in the porous structure during the cooling process after heating up to a high temperature was analyzed using the finite element method (FEM). The FEM model consists of a hexagonal body with circular pores arranged in an organized pattern and has consistent pore distances. Three pore sizes were examined to observe the stress distribution while cooling from 800 to 25 ℃. The study revealed that stress is caused by material expansion at high temperatures and rapid shrinkage at lower temperatures, leading to stress concentration. Additionally, the research shows that porous materials with smaller pores have a higher stress distribution compared to those with larger pores.