Dynamic Response and Damage Mechanism of Two-Core Composite Sandwich Panels under Low-Velocity Impact

2013 ◽  
Vol 405-408 ◽  
pp. 2810-2814
Author(s):  
Chang Liang Li ◽  
Da Zhi Jiang ◽  
Jing Cheng Zeng ◽  
Su Li Xing

Dynamic response and damage mechanism of two-core sandwich panels with foam and honeycomb cores and glass fiber/epoxy composite sheets under low-velocity transverse impact are investigated. The emphasis is focused on the contact force response and crash mechanism of the two-core sandwich panels. Effects of configurations, impact energy levels and types of the cores on the dynamic response are investigated. A modified drop-test experiment is carried out to obtain contact force history of the two-core sandwich structures under different impact energies. The experimental results show that the 10:10 configurations for both honeycomb and foam core sandwich structures under lower impact energy absorb more impact energy than the other two structures. However, under higher impact energy, the honeycomb core sandwich structures of 15:5 configuration absorbs a little more impact energy than the other two, while for the foam core sandwich structures the 5:15 configuration shows a little better impact resistance. Results also show that when impact energy is low foam core sandwich structures do better in absorbing impact energy than the honeycomb ones.

Author(s):  
Haifu Yang ◽  
Yuansheng Cheng ◽  
Pan Zhang ◽  
Jun Liu ◽  
Kai Chen

Sandwich structures with corrugated cores have attracted a lot of interest from industrial and academic fields due to their superior crashworthiness. In this paper, the dynamic response of metallic trapezoidal corrugated core sandwich panels under low-velocity impact loading is studied by conducting drop hammer impact testing. The sandwich panels composed of two thin face skins and trapezoidal corrugated core, were designed and fabricated through folding and laser welding technology. Main attention of present study was placed at the influences of the impact energy, impactor diameter and impact location on the impact force, deformation mechanisms and the permanent deflections of the trapezoidal corrugated core sandwich panels. Results revealed that the impact energy has significant effects on the dynamic response of the sandwich panel, whereas the impact diameter has little effects on it. The deformation mode of the front face sheet differs sharply when the impact location is different. The middle unit cell of corrugated core is compressed to the “M” shape under different low-velocity impact loading.


2001 ◽  
Author(s):  
Terry Hause ◽  
Liviu Librescu

Abstract This paper addresses the problem of the dynamic response in bending of flat sandwich panels exposed to time-dependent external pulses. The study is carried out in the context of an advanced model of sandwich structures that is characterized by anisotropic laminated face sheets and an orthotropic core layer. A detailed analysis of the influence of a large number of parameters associated with the particular type of pressure pulses, panel geometry, fiber orientation in the face sheets and, presence of tensile uni/biaxial edge loads is accomplished, and pertinent conclusions are outlined.


Holzforschung ◽  
2018 ◽  
Vol 72 (8) ◽  
pp. 681-689 ◽  
Author(s):  
Mostafa Mohammadabadi ◽  
Vikram Yadama ◽  
LiHong Yao ◽  
Debes Bhattacharyya

AbstractProfiled hollow core sandwich panels (SPs) and their components (outer layers and core) were manufactured with ponderosa and lodgepole pine wood strands to determine the effects of low-velocity impact forces and to observe their energy absorption (EA) capacities and failure modes. An instrumented drop weight impact system was applied and the tests were performed by releasing the impact head from 500 mm for all the specimens while the impactors (IMPs) were equipped with hemispherical and flat head cylindrical heads. SPs with cavities filled with a rigid foam insulation material (SPfoam) were also tested to understand the change in EA behavior and failure mode. Failure modes induced by both IMPs to SPs were found to be splitting, perforating, penetrating, core crushing and debonding between the core and the outer layers. SPfoams absorbed 26% more energy than unfilled SPs. SPfoams with urethane foam suffer less severe failure modes than SPs. SPs in a ridge-loading configuration absorbed more impact energy than those in a valley-loading configuration, especially when impacted by a hemispherical IMP. Based on the results, it is evident that sandwich structure is more efficient than a solid panel concerning impact energy absorption, primarily due to a larger elastic section modulus of the core’s corrugated geometry.


Author(s):  
K. Malekzadeh ◽  
M. R. Khalili

Dynamic response of sandwich panels with a flexible core under simultaneous low-velocity impacts of multiple small masses has investigated in this paper. The contact forces between the panel and the impactors are treated as the internal forces of the system. Shear deformation theory is used for the face sheets while three dimensional elasticity is used for the soft core. The fully dynamic effects of the core layer and the face-sheets are considered in this study. The results in multiple mass impacts over sandwich panels are presented based on proposed improved higher-order sandwich plate theory (IHSAPT). As no literature could be found on the impact of multiple impactors over sandwich panels, the present formulation is validated indirectly by comparing the response of two cases of double small masses and single small mass impacts based on Olsson’s wave control principle.


Sign in / Sign up

Export Citation Format

Share Document