scholarly journals NUMERICAL SIMULATIONS OF QUASI-STATIC INDENTATION AND LOW VELOCITY IMPACT OF ROHACELL 51 WF FOAM

2014 ◽  
Vol 11 (supp01) ◽  
pp. 1344004 ◽  
Author(s):  
E. A. FLORES-JOHNSON ◽  
Q. M. LI ◽  
LUMING SHEN
Keyword(s):  
Numerical Simulations ◽  
Material Model ◽  
Low Velocity Impact ◽  
Resistance Force ◽  
Low Velocity ◽  
Velocity Impact ◽  
Rate Dependent ◽  
Numerical Predictions ◽  
Static Indentation ◽  
Impact Simulations

Numerical simulations of quasi-static indentation and low velocity impact of low density polymethacrylimide (PMI) Rohacell 51 WF foam using indenters with different nose shapes (conical, truncated-conical, hemi-spherical and flat) were carried out using the finite element code LS-DYNA. A 2D axisymmetric model was generated. A strain-rate dependent material model and r-adaptive remeshing were used for low velocity impact simulations. Numerical predictions matched the available experimental data very well. Moreover, the predicted resistance force closely matched the empirical results. The results demonstrated the ability of the model to reproduce the deformation mechanisms of the penetration process of Rohacell 51 WF foam.

scholarly journals A Strain Rate Dependent Progressive Damage Model for Carbon Fiber Woven Composites under Low Velocity Impact

2021 ◽  
Vol 2101 (1) ◽  
pp. 012073
Author(s):  
Xueyao Hu ◽  
Jiaojiao Tang ◽  
Wei Xiao ◽  
Kepeng Qu
Keyword(s):  
Strain Rate ◽  
Damage Model ◽  
Low Velocity Impact ◽  
Woven Composites ◽  
Progressive Damage ◽  
Low Velocity ◽  
Velocity Impact ◽  
Rate Dependent ◽  
Plane Direction ◽  
Progressive Damage Model

Abstract A progressive damage model was presented for carbon fiber woven composites under low velocity impact, considering the strain rate sensitivity of both mechanical properties and failure mechanisms. In this model, strain rate dependency of elastic modulus and nominal strength along in-plane direction are considered. Based on the Weibull distribution, stiffness progressive degradation is conducted by introducing strain rate dependent damage variables for distinct damage modes. With the model implemented in ABAQUS/Explicit via user-defined material subroutine (VUMAT), the mechanical behavior and possible damage modes of composites along in-plane direction can be determined. Furthermore, a bilinear traction separation model and a quadratic stress criterion are applied to predict the initiation and evolution of interlaminar delamination. Comparisons are made between the experimental results and numerical simulations. It is shown that the mechanical response and damage characteristics under low velocity impact, such as contact force history and delamination, are more consistent with the experimental results when taken the strain rate effect into consideration.

scholarly journals Ultrasonic Analysis of Damage in CFRP Resulting from Static Indentation and Low Velocity Impact

1993 ◽  
Vol 2 (3) ◽  
pp. 096369359300200
Author(s):  
H. Kaczmarek
Keyword(s):  
Impact Testing ◽  
Low Velocity Impact ◽  
Ultrasonic Tomography ◽  
Transverse Impact ◽  
Low Velocity ◽  
Velocity Impact ◽  
Testing Procedures ◽  
Damage Initiation ◽  
Static Indentation ◽  
The Impact

In order to reduce hidden damage caused in CFRP by low velocity transverse impact, testing procedures must be established by understanding the impact phenomena and the roles of various parameters on damage initiation and growth. Hence, composite plates were stressed and an original method, “ultrasonic tomography,” was applied to detect delaminations on the interfaces. The results show the similarity of the damage growth resulting from static indentation and low velocity impact.

Low-Velocity Impact Characteristics of Carbon Fiber Composites Lattice Core Sandwich Structures

2009 ◽  
Vol 79-82 ◽  
pp. 127-130 ◽  
Author(s):  
Shi Xun Wang ◽  
Lin Zhi Wu ◽  
Li Ma
Keyword(s):  
Carbon Fiber ◽  
Sandwich Structures ◽  
Impact Damage ◽  
Composite Plates ◽  
Fiber Composites ◽  
Low Velocity Impact ◽  
Carbon Fiber Composites ◽  
Low Velocity ◽  
Velocity Impact ◽  
Numerical Predictions

Since composite sandwich structures are susceptible to low-velocity impact damage, a thorough characterization of the loading and damage process during impact is important. In the present paper, the low-velocity impact response of carbon fiber composites lattice structures are investigated by experimental and numerical methods. Impact tests on composite plates are performed using an instrumented drop-weight machine (Instron 9250HV) and a new damage mode is observed. A three-dimensional finite element model is built by ABAQUS/Explicit and user subroutine (VUMAT) to predict the peak loading and simulate the complicated damage problem. It can be found that numerical predictions coincide well with experimental results.

Experimental and Numerical Investigation of Response of Sandwich Composite Beam Subjected to Low-Velocity Impact

2015 ◽  
Vol 732 ◽  
pp. 239-246 ◽  
Author(s):  
Tomáš Mandys ◽  
Vladislav Laš ◽  
Tomáš Kroupa ◽  
Robert Zemčík
Keyword(s):  
Composite Beam ◽  
Progressive Failure ◽  
Material Model ◽  
Low Velocity Impact ◽  
Elastic Behavior ◽  
Sandwich Composite ◽  
Low Velocity ◽  
Velocity Impact ◽  
Non Linear ◽  
Force Time

This paper deals with the progressive failure analysis of sandwich composite beam loaded with transversely low-velocity impact. A user defined material model was used for modeling of the non-linear orthotropic elastic behavior of composite skin. The non-linear behavior of foam core was modeled using Low-Density Foam material model. The numerical model was validated using performed experiment and the results in terms of deflection and contact force time dependencies are mutually compared.

An experimental study on quasi-static indentation, low-velocity impact and damage behaviors of laminated composites at high temperatures

2021 ◽  
pp. 096739112110169
Author(s):  
Akim Djele ◽  
Ramazan Karakuzu
Keyword(s):  
Impact Test ◽  
Laminated Composites ◽  
Low Velocity Impact ◽  
Fiber Reinforced ◽  
Transverse Loading ◽  
Low Velocity ◽  
Static Tests ◽  
Velocity Impact ◽  
Impact Tests ◽  
Static Indentation

Nowadays, fiber reinforced laminated composites are widely used in many applications due to their high strength/weight ratio. However, these materials are very sensitive to transverse loading. The low-velocity impact test has been widely used by researchers to simulate the transverse loading. However, the low-velocity impact tests are highly toilsome, and this test requires expensive hardware and software systems. To reduce the experimental costs of the low-velocity impact test, it will be more attractive, much simpler, cheaper and more widely available to achieve impact behavior using quasi-static tests. Thus, to compare both tests, in this work the absorbed energy and force-deflection curves obtained by low-velocity impact and quasi-static indentation loading in two different fiber reinforced epoxy composites have been investigated. The Carbon-Kevlar hybrid fabrics and S2 glass fabrics were used as reinforcements. For low-velocity impact tests, a range of energies was used between 20 and 80 J. For quasi-static indentation test, the crosshead speeds were increased gradually from 1 mm/min to 60 mm/min. In addition, tests at 23°C, 40°C, 60°C and 80°C were made to examine the effect of temperature on these tests. As a result of the quasi-static tests performed, the amount of energy required to perforate the samples at a certain test speed is at the same level as the low-velocity impact test. Thus, the required energy amount for the perforation of the materials can be found by performing a quasi-static test at an appropriate speed, rather than the low-velocity impact test.

Sign in / Sign up

Export Citation Format

Share Document