Abstract
Chemical stresses in a long rectangular bar were investigated. The processes of constant average concentration and constant surface concentration were considered. The concentration was obtained in analytic form and the stresses were calculated by the finite difference method. The concentration along the x 1 axis at a given time decreases with increasing aspect ratio. The effect of aspect ratio on concentration is more pronounced as the time increases, but the effect of aspect ratio is most pronounced at intermediate times. The aspect ratio influences more the stress for a constant surface concentration than for a constant average concentration. When the aspect ratio exceeds four, the stress developed in the specimen cannot be distinguished.