Fiber Ply Orientation Research Articles

The role of the fiber ply configurations on the biomechanics of the hip prosthesis

The total hip replacement is the only approved procedure for restoring a degenerated hip joint through operation. The life span of a prosthesis could depend on the geometry and material properties of the implant. This study aims to analyze the biomechanics of the carbon/polyetheretherketone (PEEK) composite prosthesis having three different fiber ply configurations compared to traditional stainless steel (SS) ones. The implant-bone system was established and subjected to a load from the head of the femur and abductor muscle sides. The stresses and strains in the implant-bone systems were calculated and compared. The results revealed lower stresses and strains in composite prostheses compared to SS ones. The fiber ply orientation of the carbon/PEEK composite prosthesis is shown to be a key asset in stress and strain distribution of the 13 implant-bone systems. The fiber plies which orientated multidirectionally with −45 and +45 degrees exhibited uniform stress and strain distributions. The results suggested the advantage of using composite prostheses in implant designs as they not only invoke lower stresses and strains in the implant-bone system but also amplify the life span of implants in the body.

Experimental study on the crashworthiness response of hybrid Al/GFRP crash-box structures under axial compression loading

In this research, the dynamic crushing behavior of crash boxes made of aluminum reinforced with Glass Fiber Reinforced Polymer (GFRP) with circular cross-section is presented. Energy absorption capacity and damage behavior for different composite wall thickness and fiber ply orientation were investigated. The result shows that adding composite layers to the aluminum column will improve the column’s energy absorption capacity. Nevertheless, the Specific Energy Absorption (SEA) of the aluminum structures generally higher than the hybrid systems. However, the hybrid column has higher crushing resistance than a combination of separate aluminum and composite crash boxes with the same geometry. This shows that interaction between aluminum and composites enhance the crash behavior since a stable and progressive crushing mode were observed, resulting in greater energy absorption. Additional research should be carried out to investigate further.

Finite element analysis of drilling unidirectional CFRP in different ply orientation

In the new era of Industrial Revolution 4.0 (IR 4.0), the manufacturing processes are facing a new level of flexible mass production technologies. Hence, the high demands for simulations data of manufacturing production and operation are required for developing a Cyber-Physical Systems of smart machines. Some composite machining processes could be very expansive. Simulation is needed to reduce the manufacturing time and cost. Without considering the suitable parameter of drilling, damage occurs at the region over the hole’s boundary after the drilling operation is done. Thus, the goal of this research is to investigate the effects of drilling cutting parameter such as thrust force, drilling-induced damage and stress distribution of reinforcing carbon composite polymer (CFRP) laminate by developing a user-defined material model (VUMAT) subroutine in ABAQUS/EXPLICIT (ABAQUS, Dassault Systèmes®) for different fibre ply orientations. The failure mode such as fibre tensile failure, fibre compressive failure, matrix cracking and matrix crushing was modelled and analysed based on Hashin and Puck’s criterion. The stages of drilling operation were observed and described in this paper with the drilling cutting parameter and the damage of composite was finely defined. The results proved that the relationship of thrust force is directly proportional to the feed rate with the difference of computational model are 8 % higher than the experiment. Among the ply orientation sequence applied in the simulation, the result shows that [ / / ] and [ / / ] ply having higher thrust force with 401.84 N.mm and 390.53 N.mm at 500 mm/min feed rate as delamination extent, as the frequency of fiber pulls out at the exit region of the drilled hole increases as compared to the restricted fiber ply orientation 0˚ and 90˚.

The effects of fiber ply orientation, laminate layer and PLA content on mechanical properties of carbon fiber reinforced bioplastic composites

In this study, two kinds of bioplastic materials, where the first consists of 10% PLA, corn starch of 80% and CaCO3 10%, and the second consists of 45% PLA content, corn starch of 45% and CaCO3 10%, were used. The composites were also reinforced by the carbon fibers, which were prepared with one and two layers of carbon fiber and then ply orientations of [0[Formula: see text]] and [45[Formula: see text]]. The maximum tensile strength was observed for PLA 45% with a [0[Formula: see text]] ply orientation of two layers of carbon fiber. For composite with two layers of carbon fiber, the tensile strength showed higher for the [0[Formula: see text]] ply orientation than for the [45[Formula: see text]] ply orientation. The fatigue strength strongly depends on the orientation of carbon fiber, but in the long fatigue life range, the difference of fatigue strength between the fiber ply orientations reduces.

Buckling analysis of unitized curvilinearly stiffened composite panels

Innovative manufacturing technology has led to the fabrication of complex shape and multi-functional structures by using the concept of integrated and bonded unitized structural components. To study the stability behavior of such structural designs, this paper presents an efficient finite element buckling analysis of unitized stiffened composite panel stiffened by arbitrarily shaped stiffeners. A first-order shear-deformation theory is employed for both the panel and the stiffeners. Displacement compatibility conditions are imposed at the panel-stiffeners interfaces. To obviate remeshing when the stiffener shape changes, the stiffeners’ geometry and displacement are expressed in terms of those of the panel middle surface through compatibility conditions that make use of the interpolation polynomials employed in the finite element method. To accommodate any shaped stiffeners, a generalized geometry parametrization tool is developed to parameterize the shape of the stiffeners including the stiffener placement and the stiffener geometric curvature. Convergence and validation studies using the present method for the buckling analysis of stiffened isotropic and composite panels are conducted to illustrate the accuracy of the present method. Parametric studies show that the stiffener placement, the stiffener geometric curvature, the stiffener depth ratio (height-to-width ratio) and laminates fiber ply orientation influence both the plate bucking load and the correspond buckling mode shape. The tailoriability of the stiffeners shape and the laminates fiber ply orientation provides an enhanced design space in the structural design for improving the structural stability.

Modeling and Contact Analysis of Composite (FRP) Material Lamination on Cylindrical Roller Bearing

Fiber reinforced polymer (FRP) composites are an important class of tribological materials. They possess unique self -lubrication capabilities and low noise which make them suitable for applications like seals, bearings, gears and artificial prosthetic joints. The FRP composite bearings are ideal for high load low speed applications or where normal lubrication is difficult or costly. The friction and wear behavior of FRP composites varies with fiber orientation and sliding direction. For the purpose of fully utilizing the beneficial contact characteristics of FRP composite, it is necessary to obtain an in-depth knowledge of their contact behavior. In this work, the compliance behavior of FRP composite bearings is studied. The frictional sliding contact between a FRP composite and a rigid parabolic cylinder is analyzed. The influence of sliding direction, fiber and matrix material combinations, volume fraction of the fiber, frictional coefficient and fiber ply orientation on the contact pressure distribution and the contact area for unidirectional FRP composite bearings are evaluated. A finite element model is developed using ANSYS12.0 and the results obtained from the analysis are compared with the analytical results. The influence of sliding direction on the contact pressure distribution for cross FRP composite bearings is studied and compared with unidirectional FRP composite bearings.

Effect of Moisture Absorption and Fiber Ply Orientation for Artificial Hip Joint on the Mechanical Properties of Carbon/PEEK Composites

The purpose of this study is to determine the correct estimation of the mechanical property between epoxy resin and PEEK sheet as the composites and its validity has been tested with the alternative materials of the metal-based materials for artificial hip joint. Moreover, this work evaluated the mechanical properties according to the moisture absorption and the fractured surfaces of Carbon/Epoxy and Carbon/PEEKcomposites were also evaluated. First, the specimens for the Carbon/PEEK and Carbon/Epoxy composites manufactured with the ASTM standard. The specimens immersed in distilled water at 37°C during 100 days and the coefficient of moisture was measured in according tothe Fick's law. In addition, this work evaluated the fracture energy according to the fiber ply orientation. As a result, the coefficient ofmoisture-absorption of Carbon/PEEK composites was the lowest because the interface coherence with the fiber and resin are the most strong. Also, the fracture energy of the Carbon/PEEK composites was more excellent than the Carbon/Epoxy composites.

Design of Artificial Hip Joint by Carbon/PEEK Composites

The purpose of this study is to determine the correct estimation of the various designs for artificial hip joint of the Carbon/PEEK composites. Validity of the study has been tested with the alternative materials for the metal-based materials for artificial hip joint. Moreover, this work evaluated the FEA according to the fiber ply orientation and the condition of load. The stem shape of two kinds was designed through the normal shape of the femur. Three load cases of 1kN, 2.5kN and 5kN were used for each of FEA model. In the case of general shape, the results by ply configuration showed that the stress of ply configuration I was lower compared to ply configuration II and III. On the other hand, in the case of curved shape, ply configuration II were lower compared to ply configuration I and III. The result was checked that the stress of curved shape was higher than that of the general shape in the load of 2.5kN. It could be confirmed then that a similar phenomenon would occur in the condition of 5kN load. However, in the case of ply configuration II, the stress of the curved shape was lower than the stress of the general shape.

Comparison of Mechanical Properties between Carbon/PEEK Composites and Ti Stem for Optimal Design

This study, a new concept design of the stem and aims to determine the suitability of various carbon/PEEK composite designs for artificial hip joints. Shear stress tested with alternative materials of the Ti-based stem for artificial hip joints. In addition, FEA is conducted according to the fiber ply orientation and the load condition for carbon/PEEK composites. The stem shape of two types was designed through the shape normal of the femur. Multidirectional load cases were used for each FEA model. In the case of general shape, the results show that the stress of ply orientation case II was lower than for cases I and III. On the other hand, in the case of the curved shape, ply orientation case I was lowest. In the case of the Ti stem, the stress of the curved shape was 18% lower than the general shape.

Tribological Properties of Carbon/PEEK Composites

In this study, the effect of Carbon/PEEK composites on the tribological properties has been investigated. Also, its validity has been tested in the capacity of alternative materials of the Ti-based materials used for artificial hip joint. Moreover, this work evaluated the mechanical properties according to the fiber ply orientation, along with the fractured surfaces of the carbon/PEEK composites. The composites with a unidirectional orientation had higher tribological properties than those with a multidirectional orientation. This was caused by the debonding between the carbon fiber and the PEEK, which was proportional to the contact area between the sliding surface and the carbon fiber. The friction test results showed that there were no significant differences in relation to the fiber ply orientation. However, the friction properties of the carbon/PEEK composites were higher than those of the carbon/epoxy composites. In addition, the results showed that a composite that slid in a direction normal to the prepreg lay-up direction had a smaller friction coefficient than one that slid in a direction parallel to the prepreg lay-up direction.

Friction and Wear Behavior of Carbon/PEEK Composites according to Sliding Velocity

This study was to correctly estimate the friction and wear behavior of carbon fiber and PEEK sheet composites, and the validity of using them as alternatives to the metal-based materials used for artificial hip joints. Moreover, this work evaluated the friction coefficient according to the fiber ply orientation, along with the fractured surfaces of the carbon/PEEK composites. The unidirectional composites had higher friction coefficients than those multidirectional composites. This was caused by the debonding between the carbon fiber and the PEEK sheet, which was proportional to the contact area between the sliding surface and the carbon fiber. The friction test results showed that there was no significant differences in relation to the fiber ply orientation. However, in a case where the speed was 2.5 m/s, the friction coefficient was relatively large for configuration I. The friction surface of the specimen was analyzed using an electron microscope. In all cases, the debonding of the fiber and PEEK could be confirmed.

Mechanical Properties of Carbon/PEEK Composites According to the Fiber Ply Orientation and Sizing Removal of Carbon Fiber for Artificial Hip Joint

The purpose of this study is to determine the correct estimation of the mechanical property between epoxy resin and PEEK sheet as the composites and its validity has been tested with the alternative materials of the metal-based materials for artificial hip joint. Moreover, this work evaluated the mechanical properties according to the temperature of heat treatments for sizing removal of carbon fiber and the fractured surfaces of Carbon/Epoxy and Carbon/PEEK composites were also evaluated. First, the sizing removal of carbon fiber were conducted at 300°C for 4 hours and 400°C for 2 hours. The fractured surface in the specimen of tensile test made from PEEK and epoxy resin was observed by SEM. the fracture surface of the tensile test specimen of the Carbon/Epoxy composites heat-treated to 400°C showed that the resin did not bury nearly in the fiber surface and pull out was observed. It is shown that 400°C is suitable for the sizing removal of the carbon fiber. The mechanical test result showed that there was no significant differences in short beam strength. However, the tensile strength and compressive strength of the Carbon/PEEK composites was higher than those of the Carbon/Epoxy composites in the case of the Vacuum Bag process. In addition, this result showed that the sizing material did not have a significant effect on the strength of the Carbon/PEEK composites.

Experimental and analytical assessment of axial crushing of circular hybrid tubes under quasi-static load

In the present article, axial crushing behavior of circular aluminum/glass–epoxy hybrid tubes is studied experimentally and analytically. 48 quasi-static axial crushing experiments are carried out on bare metal and hybrid tubes to evaluate the effect of different parameters such as metal and composite wall thicknesses and stacking sequence of composite layers on the crashworthiness characteristics. The specimens are made in two types of layups including angle ply pattern [±θ]s and multi angle ply pattern (different ply angles). The experimental results reveal that stacking sequence has a considerable effect on crashworthiness characteristics, for example for layup [90/0/0/90], the absorbed energy is more than three times of aluminum tube with the same aluminum wall thickness. Also the aforementioned layup has better energy absorption compared to [90/90/90/90] which has been previously proposed as the best layup.According to considerable effect of stacking sequence on the axial crushing behavior of hybrid tubes, an analytical model is developed by including fiber ply orientation of each composite layer and an expression is derived for the mean crushing load and fold length in terms of thicknesses of metal and composite walls and material properties of metal and composite. This model shows reasonably good agreement with experimental results.

Optimisation of Contact Parameters of Unidirectional FRP Composite Bearings

The contact characteristics of unidirectional continuous fiber-reinforced plastic (FRP) composite bearings are investigated based on Hwu and Fan's closed form analytical solution. The particular condition of a rigid parabolic cylinder in frictional sliding contact with the composite is evaluated. The influences of sliding direction, fiber material, matrix material, fiber volume fraction and fiber ply orientation on the surface contact pressure are determined and compared with published results. From the analytical results, several important trends for the contact behavior of FRP composite bearings are discussed. The contact parameters for unidirectional FRP composite bearings are optimized using genetic algorithm. The study shows that, in case of unidirectional FRP composite bearings, the highest maximum contact pressure is obtained in the normal direction and hence, the normal direction has the highest wear resistance. It is also observed that increasing the volume fraction of fibers increases the maximu...

Numerical Study on Hybrid Tubes Subjected to Static and Dynamic Loading

The commercial finite element program LS-DYNA was employed to evaluate the response and energy absorbing capacity of cylindrical metal tubes that are externally wrapped with composite. The numerical simulation elucidated the crushing behaviors of these tubes under both quasi-static compression and axial dynamic impact loading. The effects of composite wall thickness, loading conditions and fiber ply orientation were examined. The stress–strain curves under different strain rates were used to determine the dynamic impact of strain rate effects on the metal. The results were compared with those of a simplified analytical model and the mean crushing force thus predicted agreed closely with the numerical simulations. The numerical results demonstrate that a wrapped composite can be utilized effectively to enhance the crushing characteristics and energy absorbing capacity of the tubes. Increasing the thickness of the composite increases the mean force and the specific energy absorption under both static and dynamic crushing. The ply pattern affects the energy absorption capacity and the failure mode of the metal tube and the composite material property is also significant in determining energy absorption efficiency.

Axial impact behavior and energy absorption efficiency of composite wrapped metal tubes

Axial impact crushing behavior and energy absorption efficiency of glass/epoxy composite externally wrapped circular metal tubes have been studied in this paper. Predicted instantaneous velocity and displacement formulae are presented and compared with experimental results. Four typical collapse modes are identified, and effects that contribute to the energy absorption capability, such as strain rate, composite wall thickness, fiber ply orientation, and mechanical properties of metals, are studied. By including the influence of the material strain rate effects on metals, the simplified analytical model proposed by Hanefi and Wierzbicki has been extended to impact loadings.