One step foamed plastic sandwich structure manufacture involves placing sheet molding compound(SMC) facing layer and foamable SMC core in a tool, expansion of foam and cross-linking of facing and core layers

摘要

A SMC(sheet molding compound) facing layer and other initial materials are placed in layers in a molding tool and are precompressed in the heated tool. During the precompression period a blowing agent is activated and at least one of the initial material layers starts to foam. A SMC(sheet molding compound) facing layer and other initial materials are placed in layers in a molding tool and are precompressed in the heated tool. During the precompression period a blowing agent is activated and at least one of the initial material layers starts to foam. After pre-compression partial opening of the tool to the final product thickness allows the foaming material to expand and form a core layer. With the tool cavity held at the final molding thickness all cross-linkable materials are hardened.