The response of honeycomb sandwich panels under low-velocity impact loading

Abstract This paper describes the results of an experimental investigation and a numerical simulation on the impact damage on a range of sandwich panels. The test panels are representative of the composite sandwich structure of the engine nacelle Fan Cowl Doors of a large commercial aircraft. The low-velocity impact response of the composites sandwich panels is studied at five energy levels, ranging from 5 to 20 J, with the intention of investigating damage initiation, damage propagation, and failure mechanisms. These impact energy levels are typically causing barely visible impact damage (BVID) in the impacted composite facesheet. A numerical simulation was performed using LS-DYNA3D transient dynamic finite element analysis code for calculating contact forces during impact along with a failure analysis for predicting the threshold of impact damage and initiation of delaminations. Good agreement was obtained between numerical and experimental results. In particular, the numerical simulation was able to predict the extent of impact damage and impact energy absorbed by the structure. The results of this study is proving that a correct numerical model can yield significant information for the designer to understand the mechanism involved in the low-velocity impact event, prior to conducting tests, and therefore to design a more efficient impact-resistant aircraft structure.

[1]  Serge Abrate,et al.  Impact on Laminated Composites: Recent Advances , 1994 .

[2]  Werner Goldsmith,et al.  An experimental study of energy absorption in impact on sandwich plates. , 1992 .

[3]  Anthony J. Vizzini,et al.  The Buckling of a Delaminated Sublaminate on an Elastic Foundation , 1987 .

[4]  K. Y. Lam,et al.  Behavior of Uniform Anisotropic Beams of Rectangular Section under Transverse Impact of a Mass , 1997 .

[5]  Jiann-Wen Ju,et al.  A Micromechanical Damage Model for Uniaxially Reinforced Composites Weakened by Interfacial Arc Microcracks , 1991 .

[6]  Arun Shukla,et al.  Intersonic crack propagation in bimaterial systems , 1998 .

[7]  Ares J. Rosakis,et al.  Impact failure characteristics in sandwich structures. Part II: Effects of impact speed and interfacial strength , 2002 .

[8]  K. E. Simmonds,et al.  Low-Velocity Impact Response of Foam-Core Sandwich Composites , 1992 .

[9]  Marshall Rouse,et al.  Evaluation of a Composite Sandwich Fuselage Side Panel With Damage and Subjected to Internal Pressure , 1997 .

[10]  Wesley J. Cantwell,et al.  The low velocity impact response of foam-based sandwich structures , 2002 .

[11]  A. T. Nettles,et al.  On the enhancement of impact damage tolerance of composite laminates , 1993 .

[12]  J. Vinson.  The Behavior of Sandwich Structures of Isotropic and Composite Materials , 1999 .

[13]  R. R. Aitken,et al.  Modelling of Crushing Due to Impact in Honeycomb Sandwiches , 2000 .

[14]  Robert Mines.  Impact Energy Absorption of Polymer Composite Sandwich Beams , 1997 .

[15]  M. D. Rhodes,et al.  Impact fracture of composite sandwich structures , 1975 .

[16]  Their Composites,et al.  Composite Materials: Testing and Design (Eighth Conference) , 1988 .

[17]  Tsu-Wei Chou,et al.  Characterization and modeling of microcracking and elastic moduli changes in Nicalon/CAS composites , 1993 .

[18]  Isaac M Daniel,et al.  Progressive Transverse Cracking of Crossply Composite Laminates , 1990 .

[19]  X. Zhang,et al.  IMPACT DAMAGE PREDICTION IN CARBON COMPOSITE STRUCTURES , 1995 .

[20]  John Lambros,et al.  An experimental study of dynamic delamination of thick fiber reinforced polymeric matrix composites , 1997 .

[21]  George S. Springer,et al.  Measurements of Matrix Cracking and Delamination Caused by Impact on Composite Plates , 1988 .

[22]  P. Geubelle,et al.  Impact-induced delamination of composites: A 2D simulation , 1998 .

[23]  Ares J. Rosakis,et al.  Impact failure characteristics in sandwich structures: Part I: Basic failure mode selection , 2002 .

[24]  Michael Valenti,et al.  Stealth on the Water , 2001 .

[25]  K. Ravi-Chandar,et al.  An experimental investigation into dynamic fracture: III. On steady-state crack propagation and crack branching , 1984 .

[26]  Hyung Yun Choi,et al.  A New Approach toward Understanding Damage Mechanisms and Mechanics of Laminated Composites Due to Low-Velocity Impact: Part I—Experiments , 1991 .

[27]  Serge Abrate,et al.  Impact on Composite Structures , 1998 .

[28]  L. E. Malvern,et al.  Delamination-crack propagation in ballistically impacted glass/epoxy composite laminates , 1982 .

[29]  Arun Shukla,et al.  Subsonic and intersonic crack growth along a bimaterial interface , 1996 .

[30]  Ares J. Rosakis,et al.  The effect of bond strength and loading rate on the conditions governing the attainment of intersonic crack growth along interfaces , 1999 .

[31]  Shaik Jeelani,et al.  Impact response of integrated hollow core sandwich composite panels , 2000 .

[32]  Norman Jones,et al.  High velocity perforation behaviour of polymer composite laminates , 1999 .

[33]  Thomas E. Lacy,et al.  Review of Damage Tolerance for Composite Sandwich Airframe Structures , 1999 .

[34]  John Morton,et al.  The impact resistance of composite materials — a review , 1991 .

[35]  Said Rechak,et al.  Effect of Adhesive Layers on Impact Damage in Composite Laminates , 1988 .

[36]  J. W. Dally,et al.  A photoelastic analysis of stress wave propagation in a layered model , 1966 .

[37]  G.A.O. Davies,et al.  Impactor mass and specimen geometry effects in low velocity impact of laminated composites , 1992 .

[38]  Leif A. Carlsson,et al.  The Tilted Sandwich Debond (TSD) Specimen for Face/Core Interface Fracture Characterization , 1999 .

[39]  A. G. Gibson,et al.  The static and impact behaviour of polymer composite sandwich beams , 1994 .

[40]  Ares J. Rosakis,et al.  An experimental study of impact-induced failure events in homogeneous layered materials using dynamic photoelasticity and high-speed photography , 2003 .

[41]  Chun-Gon Kim,et al.  Impact Resistance of Composite Laminated Sandwich Plates , 1992 .

[42]  Anthony N. Palazotto,et al.  Low-velocity impact damage initiation in graphite/epoxy/Nomex honeycomb-sandwich plates , 1998 .

[43]  Alan T. Nettles,et al.  Impact testing of glass/phenolic honeycomb panels with graphite/epoxy facesheets , 1990 .

[44]  Stephen R Reid,et al.  Indentation, Penetration and Perforation of Composite Laminate and Sandwich Panels under Quasi-Static and Projectile Loading , 1997 .

[45]  Serge Abrate,et al.  Localized Impact on Sandwich Structures With Laminated Facings , 1997 .

[46]  B. Z. Jang,et al.  Instrumented Impact Testing of Composite Sandwich Panels , 1989 .

[47]  Damodar Ambur,et al.  Low-speed impact response characteristics of composite sandwich panels , 1995 .

[48]  Rosenfeld,et al.  Compression Fatigue Behavior of Graphite/Epoxy in the Presence of Stress Raisers , 1981 .

[49]  D R Ambur,et al.  Compression Response of a Sandwich Fuselage Keel Panel With and Without Damage , 1997 .

[50]  L. B. Freund,et al.  Crack patterns in brittle thin films , 2000 .

[51]  M. Williams,et al.  Stress Singularities Resulting From Various Boundary Conditions in Angular Corners of Plates in Extension , 1952 .

[52]  S. Abrate.  Impact on Laminated Composite Materials , 1991 .

[53]  Z. Suo,et al.  Mixed mode cracking in layered materials , 1991 .

[54]  C. Bert,et al.  The behavior of structures composed of composite materials , 1986 .

[55]  G. Ravichandran,et al.  Experimental simulation of matrix cracking and debonding in a model brittle matrix composite , 1997 .

[56]  F. Chang,et al.  A Progressive Damage Model for Laminated Composites Containing Stress Concentrations , 1987 .

[57]  D R Ambur,et al.  Damage-Tolerance Characteristics of Composite Fuselage Sandwich Structures With Thick Facesheets , 1997 .

[58]  Fu-Kuo Chang,et al.  A Model for Predicting Damage in Graphite/Epoxy Laminated Composites Resulting from Low-Velocity Point Impact , 1992 .

[59]  M. Ortiz,et al.  Delamination of Compressed Thin Films , 1997 .