2024 年 73 巻 2 号 p. 165-171
Injection molded composites, which are increasingly being applied to automobiles, have a distribution of fiber orientation within the part, making it difficult to ensure the accuracy of structural analysis. In particular, it is necessary to correctly predict edge stresses in order to predict bending strength properties. To this end, we proposed in a previous report a coupled forming and structural analysis method that can account for heterogeneity in fiber orientation in the thickness direction, and demonstrated its superiority in three-point bending of a flat plate in the out-of-plane direction. However, we have not been able to verify the accuracy of the analysis for in-plane direction loading or the accuracy when the orientation is uniform in the plate thickness direction. Therefore, the validity of this method was verified on an H-shaped material intended for automotive parts. Talbot-Law imaging and micro X-ray CT imaging were used to ensure the accuracy of the fiber orientation tensor of the entire structure and the flange ends, and then coupled analysis was performed. The analysis error of the conventional method for both maximum generated load and rupture displacement was around 30%, whereas the new method was within 4%, confirming its significance.