During compression of porous metals, significantly large local deformations such as deformation bands could fluctuate the compressive stress. A deformation band is a series of locally deformed cell walls. Prediction of the specific location of such bands in a specimen is needed to prevent the formation of deformation bands. Calculating the stress concentration factor could be used to estimate the relative amount of local deformation. Also, performing a path search could be used to estimate the location of deformation bands. Thus, the objective of this research was to predict locally deformed cell walls and deformation bands from the initial geometry.  Porous metals with penetrating unidirectional pores were employed for the specimen since in situ observation of all cell walls is possible with them. Two cubic specimens with different edge lengths of 25 and 39 mm were prepared which will be referred to as L25 and L39. Pores were randomly distributed with maintaining a porosity of approximately 35 pct. The compressive behavior of the specimens was numerically analyzed with finite element code Abaqus/Standard, Explicit 2018.

 Porous metals with penetrating unidirectional pores were employed for the specimen since in situ observation of all cell walls is possible with them. Two cubic specimens with different edge lengths of 25 and 39 mm were prepared which will be referred to as L25 and L39. Pores were randomly distributed with maintaining a porosity of approximately 35 pct. The compressive behavior of the specimens was numerically analyzed with finite element code Abaqus/Standard, Explicit 2018.

The stress concentration factor was calculated in accordance with previous research and calibrated for each cell wall to estimate the amount of local deformation.(Howland 1935, Isida 1959) The cell walls that have a relatively large factor were mostly corresponding to the cell walls with large local deformation at the compressive strain e = 1.0 pct. Then, a path search was performed on a map of equivalent plastic strain  ε𝑝̅̅̅  at e = 1.0 pct. As a result, the path with maximum mean of ε𝑝̅̅̅ corresponded to the actual deformation band at e = 12.0 pct for L25. In contrast, there was no obvious deformation band in L39. This difference is considered to be caused by the difference in the distribution of ε𝑝̅̅̅ mean; deviation in L25 is significantly larger than that in L39 which presumably enlarged deformation selectiveness in the specimen.