Dynamic out-of-plane compressive failure mechanism of C/C composite: Strain rate effect on the defect propagation and microstructure failure

2021 ◽  
pp. 1-31
Author(s):  
Fei Guo ◽  
Qingguo Fei ◽  
Yanbin Li ◽  
Nikhil Gupta
Keyword(s):  
Constitutive Model ◽  
Strain Rate ◽  
Failure Mechanism ◽  
Maximum Stress ◽  
Testing Machine ◽  
Strain Rate Effect ◽  
Rate Effect ◽  
Compressive Failure ◽  
Macro Scale ◽  
Out Of Plane

Abstract Out-of-plane compression experiments with the strain rate from 0.0001/s to 1000/s are performed on 3D fine weave pierced Carbon/Carbon (C/C) composite using a universal testing machine, a high-speed testing machine, and a split Hopkinson pressure bar (SHPB). The compressive failure mechanism of the composite is analyzed by multi-scale analysis method, which ranges from micro-scale defect propagation, through meso-scale microstructure failure, to macro-scale material failure. In order to predict the out-of-plane compressive properties of 3D fine weave pierced C/C composite at different strain rates, a strain-rate-dependent compressive constitutive model is proposed. The results show that the out-of-plane compressive behavior of the 3D fine weave pierced C/C composite is sensitive to strain rate. With increasing the strain rate, the initial compressive modulus, the maximum stress and the strain at the maximum stress increase. The difference in mechanical behavior between quasi-static and high strain rate compression is owing to the strain rate effect on the defect propagation of the 3D fine weave pierced C/C composite. The proposed constitutive model matches well with the experimental data.

Impact Compressive Failure of a Unidirectional Carbon/Epoxy Laminated Composite in Three Principal Material Directions

2012 ◽  
Vol 706-709 ◽  
pp. 799-804 ◽  
Author(s):  
Takashi Yokoyama
Keyword(s):  
Strain Rate ◽  
Split Hopkinson Pressure Bar ◽  
Testing Machine ◽  
Laminated Composite ◽  
Strain Rate Effect ◽  
Rate Effect ◽  
Failure Behavior ◽  
Strain Rates ◽  
Compressive Failure ◽  
The Impact

The impact compressive failure behavior of a unidirectional T700/2521 carbon/epoxy laminated composite in three principal material directions or fiber (1-), in-plane transverse (2-) and through-thickness (3-) directions is investigated on the conventional split Hopkinson pressure bar (SHPB). Cubic and rectangular block specimens with identical square cross section are machined from an about 10 mm thick composite laminate. The uniaxial compressive stress-strain curves up to failure at quasi-static and intermediate strain rates are measured on an Instron testing machine. It is shown that the ultimate compressive strength and strain exhibit no strain-rate effect in the 1-direction, but a slight strain-rate effect in the 2-and 3-direction over a range of strain rates from10-3to 103/s.

Strain Rate Effect on Mechanical Behavior of Metallic Honeycombs Under Out-of-Plane Dynamic Compression

2015 ◽  
Vol 82 (2) ◽  
Author(s):  
Yong Tao ◽  
Mingji Chen ◽  
Yongmao Pei ◽  
Daining Fang
Keyword(s):  
Strain Rate ◽  
Present Model ◽  
Dynamic Compression ◽  
Strain Rate Effect ◽  
Numerical Results ◽  
Rate Effect ◽  
Plateau Stress ◽  
Parent Materials ◽  
Wide Range ◽  
Out Of Plane

Although many researches on the dynamic behavior of honeycombs have been reported, the strain rate effect of parent materials was frequently neglected, giving rise to the underestimated plateau stress and energy absorption (EA). In this paper, the strain rate effect of parent materials on the out-of-plane dynamic compression and EA of metallic honeycombs is evaluated by both numerical simulation and theoretical analysis. The numerical results show that the plateau stress and the EA increase significantly if the strain rate effect is considered. To account for the strain rate effect, a new theoretical model to evaluate the dynamic compressive plateau stress of metallic honeycombs is proposed by introducing the Cowper–Symonds relation into the shock theory. Predictions of the present model agree fairly well with the numerical results and existing experimental data. Based on the present model, the plateau stress is divided into three terms, namely static term, strain rate term, and inertia term, and thus the influences of each term can be analyzed quantitatively. According to the analysis, strain rate effect is much more important than inertia effect over a very wide range of impact velocity.

Constitutive Model of Shape Memory Alloys: One-Dimensional Phase Transformation Model

2008 ◽  
Vol 56 ◽  
pp. 84-91
Author(s):  
Tadashige Ikeda
Keyword(s):  
Phase Transformation ◽  
Constitutive Model ◽  
Shape Memory Alloys ◽  
Strain Rate ◽  
Shape Memory ◽  
Strain Rate Effect ◽  
Rate Effect ◽  
Reverse Transformation ◽  
Stress Strain ◽  
One Dimensional

A simple yet accurate macroscopic constitutive model of shape memory alloys has been developed. The features of this model are (1) energy-based phase transformation criterion, (2) one-dimensional phase transformation rule based on a micromechanical viewpoint, (3) dissipated energy with a form of a sum of two exponential functions, (4) duplication of the strain rate effect, and (5) adaptability to multi-phase transformation. This model is further improved to be able to express stress-strain relationships such that the reverse transformation starts at a higher stress than the martensitic transformation starts. Here, the ideal reversible transformation temperature is empirically described by a function of the martensite volume fraction. In this paper, an outline of our model is given, where the improvement is introduced. Then, it is shown that the model can quantitatively duplicate the major and minor hysteresis loops, strain rate effect, and asymmetry in tension and compression on the stress-strain relationship. And that it can also duplicate the stress-strain relationships having the reverse transformation start stress higher than the forward one.

Strain rate effect on the out-of-plane dynamic compressive behavior of metallic honeycombs: Experiment and theory

2015 ◽  
Vol 132 ◽  
pp. 644-651 ◽  
Author(s):  
Yong Tao ◽  
Mingji Chen ◽  
Haosen Chen ◽  
Yongmao Pei ◽  
Daining Fang
Keyword(s):  
Strain Rate ◽  
Strain Rate Effect ◽  
Rate Effect ◽  
Compressive Behavior ◽  
Out Of Plane

Strain Rate Effect on Out of Plane Shear Strength of Fiber Composites

2007 ◽  
Vol 345-346 ◽  
pp. 725-728
Author(s):  
Jia Lin Tsai ◽  
Jui Ching Kuo
Keyword(s):  
Shear Strength ◽  
Strain Rate ◽  
Shear Strain ◽  
Fiber Composites ◽  
Strain Rate Effect ◽  
Rate Effect ◽  
Strength Analysis ◽  
Shear Strain Rate ◽  
Plane Shear ◽  
Out Of Plane

This research aims to investigate strain rate effect on the out of plane shear strength of unidirectional fiber composites. Both glass/epoxy and graphite/epoxy composites were considered in this study. To demonstrate strain rate effect, composite brick specimens were fabricated and tested to failure in the transverse direction at strain ranges from 10-4/s to 700/s. Experimental observations reveal that the main failure mechanism of the specimens is the out of plane shear failure taking place on the plane oriented around 30 to 35 degree to the loading direction. The corresponding out-of-plane shear strength was obtained from the uniaxial failure stress through Mohr-Coulomb strength analysis. In addition, the associated shear strain rate on the failure plane was calculated through the coordinate transformation law. Results show that the out-plane shear strength increases with the increment of the shear train rates. A semi-logarithmic function expressed in terms of the normalized shear strain rate was employed to describe the rate dependence of the out-plane shear strength.

scholarly journals Numerical Simulation Study on Strain Rate Effect of Fiber Reinforced Composites

2020 ◽  
Author(s):  
Hui Ye ◽  
Chang Liu ◽  
Yanrong Zhu
Keyword(s):  
Constitutive Model ◽  
Strain Rate ◽  
Composite Laminates ◽  
Model Simulation ◽  
Strain Rate Effect ◽  
Rate Effect ◽  
Fiber Reinforced Composites ◽  
Reinforced Composites ◽  
Fiber Reinforced ◽  
Simulation Results

Abstract In order to study the effect of strain rate effect on the simulation precision of fiber reinforced composites, the dynamic enhancement factor (DIF) was introduced to modify the modulus and strength of the composite, and the modified Hashin failure criterion was used to establish a three-dimensional progressive damage constitutive model of composite materials which could consider the strain rate effect. The model is embedded into the Abaqus software by VUMAT subroutine, and the simulation of the projectile penetrating the fiberglass reinforced composite laminates is carried out. The simulation results are compared with the experimental results and the constitutive model simulation results without considering the strain rate effect. The results show that the constitutive model with strain rate established in this paper can accurately simulate the process of projectile penetrating the laminates. Compared with the simulation results without strain rate, the accuracy is increased in the model with strain rate, respectively by 14.1% at the penetration speed of 1.8 m/s and by 22.7% at 3 m/s. The errors, between the simulation results of without strain rate and that of the experiments, are increased with the increase of penetration speed, and increase from 28.7% of 1.8 m/s to 36.9% of 3 m/s. The simulation error of constitutive model with strain rate is relatively stable.

Stochastic Damage Constitutive Model for Concrete Considering Strain Rate Effect

2008 ◽  
Vol 400-402 ◽  
pp. 251-256
Author(s):  
Xiao Dan Ren ◽  
Jie Li
Keyword(s):  
Constitutive Model ◽  
Strain Rate ◽  
Dynamic Loading ◽  
Strain Rate Effect ◽  
Rate Effect ◽  
Constitutive Relationship ◽  
Dynamic Increase Factor ◽  
Damage Constitutive Model ◽  
Dynamic Stochastic ◽  
Stochastic Damage

The present work concentrates on the model of concrete under dynamic loading. The stochastic damage constitutive model for concrete under static loading developed by the authors’ research group is firstly reviewed in this paper. The strain rate effect is considered as viscous effect so that the dynamic generalization of the static model could be developed by analogy with viscous-plastic theory. Combined with static damage expressions, the frame work of dynamic stochastic damage constitutive relationship for concrete is established. The analytical expression of dynamic increase factor (DIF) of peak stresses under tension and compression are derived according to the present dynamic damage model. Several simulation results of concrete under static as well as dynamic loading are provided to demonstrate its capacity of reproducing the salient features experimentally observed.

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