A preventive method for forming dents in sandwich parts of large-curvature metal panels

Abstract

Belonging to aviation composite processing technologies, the invention relates to a large curvature metal panel sandwich part forming dent prevention method. According to the large curvature metal panel sandwich part forming dent prevention method provided by the invention, a metal panel sandwich part consists of a honeycomb and metal panels arranged on two sides of the honeycomb, in the process of honeycomb pretreatment and sandwich part forming, protection plates are laid on the honeycomb surface and the sandwich part surface respectively, then temperature raising and pressure raising are carried out first, then heat preservation is conducted, finally cooling and decompression curing treatment is performed, and the protection plates are then removed, thus finishing forming of the large curvature metal panel sandwich part. The method provided by the invention uses technological liner plates, adopts honeycomb performing process technological liner plates for protection and part bonding forming process technological liner plates for protection, the prepared part has a smooth surface, thus avoiding imprints caused by wrinkles formed after honeycomb performing, no honeycomb concavity and honeycomb height difference, lowering the product failure rate and scrap rate to 1%, and producing great economic benefits.

Description

technical field [0001] The invention belongs to the processing technology of aviation composite materials, and relates to a method for preventing forming dents of interlayer parts of large-curvature metal panels. Background technique [0002] At present, the metal-skinned sandwich structures used in the aerospace field are mainly honeycomb sandwich materials. For typical sandwich parts such as tail beams, the honeycomb is cut and preformed and used directly. However, due to the large curvature of complex sandwich parts such as tail beams (generally the curvature can reach 60°), the honeycomb is prone to depression during the vacuuming and forming process of the parts. And instability phenomenon, in addition, skin and honeycomb debonding, dents and other defects will occur after the part is cured, which will lead to repair or scrap of the part. [0003] However, because the composite material has been set in the metal panel, it is difficult to repair. Once a defect occurs, t...

AI Technical Summary

Problems solved by technology

For typical sandwich parts such as tail beams, the honeycomb is cut and preformed and used directly. However, due to the large curvature of complex sandwich parts such as tail beams (generally the curvature can reach 60°), the honeycomb is prone to depression during the vacuuming and forming process of the parts. And instability phenomenon, in addition, skin and honeycomb debonding, dents and other defects will occur after the part is cured, which will lead to repair or scrap of the part

[0003] However, because the composite material has been set in the metal panel, it is difficult to repair. Once a defect occurs, the part will be scrapped directly, so the loss is relatively large

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