Abstract: In order to verify the method of improving the peel strength when the large-sized, shaped-surface rigid polyurethane (PU) foam is used as the core foam, the rigid polyurethane (PU) foam with different surface processing methods is used as the research object, and the roller peel strength is used to characterize the bonding performance of the foam and the panel, the possibility of batch implementation on the surface of large-sized and special-shaped foam is evaluated by the convenience of processing, and the comprehensive material cost is evaluated by the increase of resin consumption in the processing method. Tests show that multi-axis machine tools can improve the peel strength of polyurethane (PU) foam sandwich composites by processing shallow grooves, blade deep slits, needle roll holes, etc. The method of using needle roll holes can improve the peel strength and processing. It has obvious advantages over other processing methods in terms of ease of operation and material cost. This research content has a good guiding significance for the improvement of the peel strength of polyurethane (PU) foams with larger sizes and special-shaped surfaces.

Key words: PU foam, special-shaped machined surface, peeling strength, composites