The Mechanical Property Of The Braided Kevlar Foldcore And Method For Reversely Designing Double Curvature Folded Core Structure

In this paper,we propose a method to design a folded core with the inner and outer contours as a rotationally symmetric hyperbolic curvature using the first-order Miura-derived pattern and study the relationship between the planar crease pattern and the folded configuration.Next,the conditions of rigid foldability and flat foldability are also discussed.Furthermore,this design method has be extended to multi-layer folded core.The case studies are illustrated by compiled Matlab figures and physical cardboard models.Meanwhile,a new kind of knitted aramid fiber composite(Kevlar)was used as the basic material of the folded core material.The mechanical properties of the folded core were studied by means of experiment and numerical simulation.The base material tests are experimented,the material properties are numerical simulated by means of user subroutine(VUMAT).At the same time,the preparation which includes the design of the molds,manufacture of the setups and the heating process of the folded core are discussed.Finally,the sandwich structure consisting of folded core and compressive auxiliary plates is manufactured,the compressive test is carried out and the material model is verified by the experimental data.