Experimental and numerical investigation on the impact behavior of dual-core composite sandwich panels designed for hydraulic turbine applications

2018 ◽  
Vol 185 ◽  
pp. 254-263 ◽  
Author(s):  
R. Ouadday ◽  
A. Marouene ◽  
G. Morada ◽  
A. Kaabi ◽  
R. Boukhili ◽  
...  
Keyword(s):  
Numerical Investigation ◽  
Sandwich Panels ◽  
Hydraulic Turbine ◽  
Impact Behavior ◽  
Composite Sandwich Panels ◽  
Composite Sandwich ◽  
The Impact ◽  
Dual Core

scholarly journals Effect of extreme cold temperatures on quasi-static indentation and impact behavior of woven carbon fiber epoxy composite sandwich panels with nomex honeycomb core

2021 ◽  
pp. 109963622199387
Author(s):  
Mathilde Jean-St-Laurent ◽  
Marie-Laure Dano ◽  
Marie-Josée Potvin
Keyword(s):  
Epoxy Composite ◽  
Impact Behavior ◽  
Effect Of Temperature ◽  
Cold Temperatures ◽  
Composite Sandwich Panels ◽  
Composite Sandwich ◽  
Static Indentation ◽  
Nomex Honeycomb ◽  
Extreme Cold ◽  
The Impact

The effect of extreme cold temperatures on the quasi-static indentation and the low velocity impact behavior of woven carbon/epoxy composite sandwich panels with Nomex honeycomb core was investigated. Impact tests were performed at room temperature, –70°C, and –150°C. Two sizes of hemispherical impactor were used combined to three different impactor masses. All the impact tests were performed at the same initial impact velocity. The effect of temperature on the impact behavior is investigated by studying the load history, load-displacement curves and transmitted energy as a function of time curves. Impact damage induced at various temperatures was studied using different non-destructive and destructive techniques. Globally, more damages are induced with impact temperature decreasing. The results also show that the effect of temperature on the impact behavior is function of the impactor size.

DYNAMIC IMPACT RESISTANCE OF COMPOSITE SANDWICH PANELS WITH 3-D PRINTED POLYMER SYNTACTIC FOAM CORES

2021 ◽  
Author(s):  
H. R. TEWANI ◽  
DILEEP BONTHU ◽  
H. S. BHARATH ◽  
MRITYUNJAY DODDAMANI ◽  
P. PRABHAKAR
Keyword(s):  
Impact Resistance ◽  
Syntactic Foam ◽  
Sandwich Panels ◽  
Syntactic Foams ◽  
Dynamic Impact ◽  
Impact Performance ◽  
Composite Sandwich Panels ◽  
Composite Sandwich ◽  
Back Face ◽  
The Impact

Polymer-based syntactic foams find use in the marine industry as primary structural materials due to their inherent lightweight nature and enhanced mechanical properties relative to pure HDPE. 3-D printing these materials circumvents the use of joining assemblies, enabling the production of complex shapes as standalone structures. Although the quasi-static response of these 3D printed foams has been well studied independently in recent years, their dynamic impact resistance and tolerance as potential core material for sandwich panels have not been the focus. Moreover, 3D printing is known to impart directionality in the printed syntactic foams, which may introduce failure mechanisms typically not observed in molded foams. It is therefore important to investigate the mechanics of 3-D printed syntactic foam core composite sandwich structures under impact loading and characterize their failure mechanisms for establishing dynamic impact resistance. To this end, 3-D printed syntactic foams have been developed using rasters of High-Density Polyethylene (HDPE) and Glass MicroBalloon (GMB) fillers by adopting the Fused Raster Fabrication (FFF) technique. The current study is performed to assess the impact performance of these composite foam cores based on the volume fraction of fillers and print orientation. The weight percentage of GMB fillers in printed specimens ranges from 0% to 60% in increments of 20%. This study presents the impact response of these composite sandwich panels at different energy levels, in compliance with ASTM D7136/D7136M - 20. Observations suggest that an increase in GMB % in HDPE matrix improves the impact performance in terms of the peak load of the material, but the failure behavior becomes brittle to an extent. Observing the failed specimens under a Micro-CT scanner captures the failure morphologies and helps characterize failure processes during impact. It is noticed that core materials with higher GMB content are prone to individual raster breakage and delamination at the back face, in addition to debonding between individual rasters. Specimens printed along the longer dimension (y-direction) impart more warping in the final sandwich structures than that of specimens printed along the shorter dimension (x-direction). Therefore, they are more susceptible to delamination at the back face. Addition of GMB fillers mitigate the tendency of the sandwich panels to warp.

Sign in / Sign up

Export Citation Format

Share Document