The three point bending of the Y-frame sandwich beams

Sandwich beams comprising Y-frame and corrugated cores have been manufactured by assembling and brazing together pre-folded AISI type 304 stainless steel sheets. The longitudinal axis of the cores coincides with the axis of the beams. The quasi-static three-point bending response of both simply supported and clamped beams is measured along with the indentation response of the beams placed on a rigid foundation. The investigation reveals that the initial collapse strength of the beams is governed by the indentation of the Y-frame or corrugated core for all beam geometries considered here. The simply supported beams have a softening response beyond the initial peak load while the clamped beams display a hardening response due to the longitudinal stretching of the face-sheets. The experimental investigation reveals that sandwich beams with Y-frame or corrugated cores have comparable responses for each of the loading situations considered. Additional insight into the deformation modes is obtained by three-dimensional finite element (FE) calculations