INFLUENCE OF PET CORE MATERIAL SUBTRACTIVE PROCESS TREATMENT ON MECHANICAL PROPERTIES OF SANDWICH STRUCTURE

Sandwich structures composed of PET foam core and aluminium alloy panel were taken as reserch object. In the process of fabricating sandwich structures, four types of core materials were employed. Firstly, untreated PET foam core and PET foam cores subjected to subtractive process treatment (unidirectional slotting, bidirectional slotting，and punching). Secondly, the peel resistance performance between the aluminium alloy panel and PET foam core was tested through the drum peel test, while the influence of material subtractive process on shear performance of the sandwich structures was evaluated through the pure shear test. Finally, the peel and shear failure modes, load-displacement responses, and peel and shear strengths of the structures were analysed.The results show that the peel strength between the panel and PET foam core is improved by 48.31%, 32.29%, and 16.67% respectively, compared with the untreated structure, by using bidirectional slotting, unidirectional slotting and punching processes. Although the three processing techniques cause damage to the PET foam core, they actually increase respectively the shear yield strength of the sandwich structures by 3.12%, 3.90%, and 2.92%, compared to the untreated structure.