Influence of Fiber Orientation and Volume Fraction on Tensile Strength and Fatigue Life of CARALL Hybrid Composite

2007 ◽  
Vol 353-358 ◽  
pp. 1455-1458 ◽  
Author(s):  
Han Ki Yoon

In this paper the tensile and fatigue life tests of carbon fiber-reinforced epoxy prepreg (CFRP) were conducted in order to investigate the influence of volume ratio and fiber orientation. CFRP/Al7075 laminate hybrid composite (CARALL) consists of alternating Al7075-T6 sheets and carbon epoxy prepreg (epoxy 121oC #2560). The fiber orientations of CFRP were applied to the extent of 0/90° and ±45°. The CFRP layers are 1ply, 3plies and 5plies in case of 0/90°, and 1ply and 2plies in case of ±45° of carbon fiber direction, respectively. The tensile strength decreased with the volume ratio of CFRP in both the cases of fiber orientation 0/90° and ±45°. The fatigue life is lower in large volume ratio of CFRP than in small volume ratio in both the cases of fiber orientation 0/90° and ±45°.

2013 ◽  
Vol 3 (1) ◽  
Author(s):  
Heri Sunardi ◽  
Achmad Zainuri ◽  
Agus Dwi Catur

   Almost all components, both metallic and non-metallic, experience the process of splicing (joining) with other components. Metal components can be welded, bolted and riveted. However, a special non metal materials such as composites, joining can not be done by welding. One type of connection is suitable for composite materials and keeling bolt connection.             The purpose of this study was to investigate the influence of the stage of making a hole with drilling machine and a variation of the fiber direction tensile strength of fiber-reinforced composite material with at pandan wangi polyester matrix. On stage perforation process conducted by three stages with the first stage (diameter 2, then continued with a diameter of 4 and 6 mm), stage II (diameter of 4 and then continued with a diameter of 6 mm), and stage III (diameter 6 mm). And for a variety of fiber direction using random fiber direction, the direction, and woven with 30% fiber volume fraction.              The results of this study showed an increase in tensile strength composite material fiber reinforced polyester-pandan wangi with unidirectional fiber orientation, which contained the highest tensile strength of the composite stage I in the amount of 27.20 MPa and a tensile strength composite lowest was at stage III amounting 13:00 MPa. In a composite material with random fiber orientation tensile strength decreased by 19.93% with the highest tensile strength found in stage I in the amount of 17.90 MPa and the lowest tensile strength found in stage III at 8:00 MPa. And the orientation of the woven fiber tensile strength decreased by 51.09% with the highest tensile strength is found in the first stage of 17:30 MPa and the lowest tensile strength found in stage III at 6.80 MPa.


2021 ◽  
pp. 002199832110112
Author(s):  
Qing Yang Steve Wu ◽  
Nan Zhang ◽  
Weng Heng Liew ◽  
Vincent Lim ◽  
Xiping Ni ◽  
...  

Propagation of ultrasonic wave in Carbon Fiber Reinforced Polymer (CFRP) is greatly influenced by the material’s matrix, resins and fiber volume ratio. Laser ultrasonic broadband spectral technique has been demonstrated for porosity and fiber volume ratio extraction on unidirection aligned CFRP laminates. Porosity in the matrix materials can be calculated by longitudinal wave attenuation and accurate fiber volume ratio can be derived by combined velocity through the high strength carbon fiber and the matrix material with further consideration of porosity effects. The results have been benchmarked by pulse-echo ultrasonic tests, gas pycnometer and thermal gravimetric analysis (TGA). The potentials and advantages of the laser ultrasonic technique as a non-destructive evaluation method for CFRP carbon fiber volume fraction evaluation were demonstrated.


1989 ◽  
Vol 4 (6) ◽  
pp. 1339-1346 ◽  
Author(s):  
C. T. Ho ◽  
D. D. L. Chung

Unidirectional and continuous carbon fiber tin-matrix composites were used for the packaging of the high-temperature superconductor YBa2Cu3O7–δ by diffusion bonding at 170 °C and 500 psi. Tin served as the adhesive and to increase the ductility, the normal-state electrical conductivity, and the thermal conductivity. Carbon fibers served to increase the strength and the modulus, both in tension along the fiber direction and in compression perpendicular to the fiber layers, though they decreased the strength in compression along the fiber direction. Carbon fibers also served to increase the thermal conductivity and the thermal fatigue resistance. At 24 vol. % fibers, the tensile strength was approximately equal to the compressive strength perpendicular to the fiber layers. With further increase of the fiber content, the tensile strength exceeded the compressive strength perpendicular to the fiber layers, reaching 134 MPa at 31 vol. % fibers. For fiber contents less than 30 vol. %, the compressive ductility perpendicular to the fiber layers exceeded that of the plain superconductor. At 30 vol. % fibers, the tensile modulus reached 15 GPa at room temperature and 27 GPa at 77 K. The tensile load was essentially sustained by the carbon fibers and the superconducting behavior was maintained after tension almost to the point of tensile fracture. Neither Tc nor Jc was affected by the composite processing.


Author(s):  
A Bakamal ◽  
R Ansari ◽  
MK Hassanzadeh-Aghdam

This paper presents a finite element analysis of the bending, buckling, and free vibration of the chopped carbon fiber/graphene nanoplatelet reinforced polymer hybrid composite plates. Both rectangular and circular composite plates are considered. The effective material properties of the chopped carbon fiber /graphene nanoplatelet reinforced hybrid composites are predicted using a multistep micromechanical model based on the Halpin–Tsai homogenization scheme. An inclusive microstructural assessment is accomplished by the evaluation of the influences of the volume fraction, length, thickness, and agglomeration of graphene nanoplatelets as well as the volume fraction, aspect ratio, and the alignment of the chopped carbon fibers on the mechanical behaviors of the chopped carbon fiber/graphene nanoplatelet hybrid composite plates. It is found that the bending, buckling, and vibration characteristics of hybrid composite structures are highly affected by the microstructural features. The addition of graphene nanoplatelets improves the stability of the chopped fiber-reinforced hybrid composite structures. The agglomeration of the graphene nanoplatelet into the polymer matrix leads to a degradation in the composite plate mechanical performances. Aligning the chopped carbon fibers significantly decreases the deflections, and increases the critical buckling loads and the natural frequencies of hybrid composite plates. Comparisons are conducted with the numerical results reported in literature that indicate good agreement with our results.


2020 ◽  
Author(s):  
Zhou Zhou ◽  
August G. Domel ◽  
Xiaogai Li ◽  
Gerald Grant ◽  
Svein Kleiven ◽  
...  

AbstractTraumatic axonal injury (TAI) is a critical public health issue with its pathogenesis remaining largely elusive. Finite element (FE) head models are promising tools to bridge the gap between mechanical insult, localized brain response, and resultant injury. In particular, the FE-derived deformation along the direction of white matter (WM) tracts (i.e., tract-oriented strain) has been shown to be an appropriate predictor for TAI. However, the evolution of fiber orientation in time during the impact and its potential influence on the tract-oriented strain remains unknown. To address this question, the present study leveraged an embedded element approach to track real-time fiber orientation during impacts. A new scheme to calculate the tract-oriented strain was proposed by projecting the strain tensors from pre-computed simulations along the temporal fiber direction instead of its static counterpart directly obtained from diffuse tensor imaging. The results revealed that incorporating the real-time fiber orientation not only altered the direction but also amplified the magnitude of the tract-oriented strain, resulting in a generally more extended distribution and a larger volume ratio of WM exposed to high deformation along fiber tracts. These effects were exacerbated with the impact severities characterized by the acceleration magnitudes. Results of this study provide insights into how best to incorporate fiber orientation in head injury models and derive the WM tract-oriented deformation from computational simulations, which is important for furthering our understanding of the underlying mechanisms of TAI.


2013 ◽  
Vol 750 ◽  
pp. 204-207
Author(s):  
Jia Xue ◽  
Wen Xue Wang ◽  
Yoshihiro Takao ◽  
Terutake Matsubara

This paper focus on the investigation of tensile strength and thermal residual stress in UACS/Al laminates. The UACS (unidirectionally arrayed chopped strands) is made by cutting parallel slits on unidirectional carbon fiber prepreg. Thus all of the carbon fibers in the cut prepreg are 25 mm in length. Six cases of UACS prepregs are prepared with different slit angle θ, which is the angle between slit and fiber direction, including 5.7o, 11.3o, 16.7o, 31o, 45o and 90o. A UACS/Al laminate consists of one UACS layer with four UACS plies and two aluminum layers, such as [Al/UACS4/Al]. Four pieces of UACS prepreg with alternate slit angle [θ/-θ/θ/-θ] are stacked together in the same fiber direction. Then stacked UACS/Al laminate are cured using an autoclave. Tensile tests are performed to investigate the thermal residuals stress using the yielding-point-shift method. Experiment results show that thermal residual stress is reduced in the case of UACS/Al compared with conventional CFRP/Al. Among all the cases, specimen with slit angle of 11.3o is the most impressive one with 37.7% reduction of thermal residual stress.


2011 ◽  
Vol 391-392 ◽  
pp. 345-348 ◽  
Author(s):  
Xiao Yuan Pei ◽  
Jia Lu Li

The modal properties of carbon fiber woven fabric / epoxy resin composites with different fiber orientation angles were studied by using single input single output free vibration of cantilever beam hammering modal analysis method. With the same fiber volume fraction, the different fiber orientation of the laminated composite has an effect on parameters of vibration mode of composites. The experimental results show that with the fiber orientation increasing, the natural frequency of laminated composites becomes smaller and damping ratio becomes larger. The fiber orientation smaller, the peak value of natural frequency becomes higher and the attenuating degree of acceleration amplitude becomes slower.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Ming-Yuan Shen ◽  
Tung-Yu Chang ◽  
Tsung-Han Hsieh ◽  
Yi-Luen Li ◽  
Chin-Lung Chiang ◽  
...  

Graphene nanoplatelets (GNPs) are novel nanofillers possessing attractive characteristics, including robust compatibility with most polymers, high absolute strength, and cost effectiveness. In this study, GNPs were used to reinforce epoxy composite and epoxy/carbon fiber composite laminates to enhance their mechanical properties. The mechanical properties of GNPs/epoxy nanocomposite, such as ultimate tensile strength and flexure properties, were investigated. The fatigue life of epoxy/carbon fiber composite laminate with GPs-added 0.25 wt% was increased over that of neat laminates at all levels of cyclic stress. Consequently, significant improvement in the mechanical properties of ultimate tensile strength, flexure, and fatigue life was attained for these epoxy resin composites and carbon fiber-reinforced epoxy composite laminates.


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