Manufacturing Process of Large Scale Sandwich Structure with Variable Thickness of PMI Foam Core
Composite sandwich structures are extensively used in the aerospace, wind power, sports equipment, shipbuilding, automotive and train locomotive industries in order to improve structure rigidity and reduce weight. The molding process of sandwich structure using glass cloth and fibre materials as panels has been reported in many literatures. However, few researches are found relative to the molding process of large scale sandwich structure with the characteristics of thin-walled aluminum alloy panels and variable thickness of Polymethacrylimide (PMI) foam cores. This paper describes a preformed molding process that consists of thermoforming foam core blocks, assembling blocks into a whole sandwich core, CNC machining the sandwich core according to surface models of the thin-walled aluminum alloy panels, and finally, bonding and curing panels and sandwich cores.