Investigation of Advanced Lightweight Sandwich Structural Concept

摘要

Although the sandwich panels fabricated of honeycomb core bonded between two face-sheets are very weight-efficient, their application causes many problems such as moisture retention, extensive corrosion, ineffective edge seals, unbonding of face-sheets, and time consuming and expensive repair. In an attempt to eliminate these detrimental factors, new sandwich structural concepts are introduced. These structural concepts include bidirectionally-corrugated, lattice-core, offset-corrugated, and cross-corrugated sandwich. They are variations of corrugated sandwich. The new features of all the sandwich are the provision of passageways from cell to cell for moisture drainage to reduce corrosion. The lattice-core, offset-corrugated, and cross-corrugated sandwich can be fabricated of fiber-reinforced composite materials in single cure operation without any secondary bonding. Sample specimens of lattice-core and offset-corrugated sandwich panels have been fabricated and tested to obtain their flexural and transverse shear stiffnesses. The predicted flexural and transverse shear stiffnesses of lattice-core and cross-corrugated sandwich panels are comparable to that of honeycomb sandwich panels. (MM).