Design selection for a hemispherical dimple core sandwich panel using hybrid multi-criteria decision-making methods

Abstract

The aim of this article is to determine the relationships between the essential criteria for the performance of sandwich panels and various alternative hemispherical core designs using a hybridisation technique within the multi-criteria decision-making method. A major reduction in core density reduced the structural integrity of the metal sandwich panel and promoted a significant effect of failure such as early delamination. Therefore, an effective optimisation analysis with highly precise determination is required to reduce the overall cost. The output from the finite element analysis was segregated into the nine main criteria that contributed to the sandwich panel performance. The analytical hierarchical process was used to develop a pairwise comparison matrix table and determine the weightages for each criterion. Further analysis using the technique for order preference by similarity to ideal solution (TOPSIS) was conducted to find the optimal solution for the core design. The results showed that a hemispherical dimple core design with a diameter of 6.0 mm and a depth of 3.0 mm achieved the highest-ranked closeness coefficient (CCi = 0.930 and 0.996) at both 70 and 50% of cyclic loading conditions. It was concluded that using small dimensions in the hemispherical core design configuration tends to produce better bonding strength performance in the sandwich panel, rather than configurations of larger dimensions. Hence, this method proved to be effective in determining the optimum selection, although the criteria and alternatives are intertwined, which complicates the process.