Global buckling behavior of a sandwich beam with graded lattice cores

The present study investigates the global buckling behavior of sandwich beams with graded lattice cores. The continuous equivalent theory is utilized to construct a discrete graded lattice core sandwich beam for a continuously varying gradient beam, whose material properties vary with position. A theoretical model of sandwich beams with graded lattice cores is established using the energy method. Finite element models are developed in ABAQUS to validate the theoretical results. Furthermore, four sets of specimens were manufactured and tested to validate the theoretical analysis methods used. The effects of the graded parameters and geometric parameters on the critical buckling load of sandwich beams with graded lattice cores are discussed. The graded lattice sandwich beams exhibit global buckling when the graded parameter is small, with the influence on buckling performance being minor. However, as the graded parameter increases, the graded lattice sandwich beams experience local buckling, and their buckling resistance weakens. Therefore, graded parameters that are too large and cause local buckling should be avoided in gradient design.