Experimental and Numerical Flexural Properties of Sandwich Structure with Functionally Graded Porous Materials

Abstract

Functionally graded porous materials (FGPMs) are porous structures with a porosity gradient distributed over the entire volume. They have many applications in the aerospace, marine, biomedical, automotive, and shipbuilding industries. High strength to weight and excellent energy absorption is the most important features that make these structures unique. In this paper, the flexural properties of simply-supported sandwich beams with functionally graded porous core under flexural load were evaluated experimentally and numerically based on various parameters. A three-point bending test for 3D printed sandwich specimens with porous metal core bonded with aluminum face sheets using various porosity parameters and core heights has been performed to measure the peak load and maximum deflection and explore the sandwich structure's strength. To validate the accuracy of the experimental solution, a finite element analysis (FEA) is carried out using ANSYS 2021 R1 software. Tests and FEM show that the sandwich beam behavior is closely related to porosity, power-law index, and FG porous metal core thicknesses. Experimental results indicated that at a porosity ratio of 10 %, FG core height 10 mm the maximum bending load was 573 N and maximum deflection 13.8 mm respectively. By increasing porosity to become 30% using the same geometrical parameters, the bending load was reduced by 15.4 % while the deflection exhibited a 1.4 % increase. The Numerical results for the three-point bending are compared with experimental measurements, showing a fair agreement with a maximum discrepancy of 15%.