Experimental investigation on bending behaviour of ZrO2 honeycomb sandwich structures prepared by DLP stereolithography

The ceramic honeycomb sandwich structures of 3 mol% yttria-stabilized tetragonal ZrO2 (3Y-TZP) material were fabricated by an additive manufacturing technique based on the digital light processing (DLP) system. The bending behaviour of hexagonal and square honeycomb sandwich structures was investigated with three-point bending test. The effects of geometric parameters, including the thickness of the face-sheet, the height of the cell, the thickness of the cell wall and the size of the cell, were studied through experiments carefully. The results illustrated that the bending strength of the ceramic honeycomb sandwich structure can reach 170 MPa at a relative density of 41.72%. The geometric parameters of the honeycomb core were more critical than the sandwich face-sheet. The cell size, cell wall thickness and cell height were found to be the preferred geometric parameter for justifying the bending resistance performance of the ceramic sandwich panel. Square honeycomb demonstrated better bending performance than the hexagonal honeycomb. This study provides a new basis for further studies on the ceramic lightweight structures.