Layered silicate composites having phenolic matrix were prepared by melt intercalation. The resole resin was synthesized and was characterized by FTIR spectroscopy. Method for making composites consisted of mechanically mixing the modified montmorillonite clay with phenol formaldehyde resin and curing the polymer to form a composite material, via intercalation of polymer in between the clay galleries. The objective was to investigate the effect of clay percentage on the behavior of composites samples. Composite samples with different clay percentages (0–4%) were compared with pristine resin sample. The morphology of the composites was examined by using scanning electron microscope (SEM) and interesting observation was made from tensile fractured sample because of formation of dendrites at 0.8 wt% clay. The crystalline and amorphous behavior was investigated by using X-ray diffraction method. The XRD pattern showed that there was a decrease in amorphous behavior with increasing filler content. Although exfoliation cannot be claimed, but improvement in mechanical properties confirm intercalation. Tensile and flexural modulus increased up to 84 and 46%, respectively, of the initial value with increase in filler content up to 0.8%, after which there was a downward trend due to possible agglomeration of clay particles.

The present work investigates the mechanical properties of conventional and hybrid composites based on epoxy resin. Diglycidyl ether of bisphenol A was used as the matrix and triethylenetetramine was used as the curing agent. Polyurethane (PUR) used was based on polyether and toluene diisocyanate. Impact strength (IS), critical stress intensity factor (K_c), tensile strength (TS) and flexural strength were evaluated as function of modifiers content. It is shown that IS is increased by approximately 120% and 200% with the addition of respectively 10 phr of glass beads (GB) or 10 phr PUR, in comparison with IS of the unmodified epoxy resin. Moreover, K_c was increased by approximately 20% with 10 phr GB and 35% with 10 phr PUR. The addition of 15 phr PUR gave compositions with 30% enhanced TS and 40% increased tensile strain at break. However, the strain at break decreased with increasing amount of GB. Hybrid composition containing 10 phr PUR and 15 phr GB exhibited the maximum tensile energy to break corresponding to 80% and 85% improvement respectively in relation to the energy at break of the virgin epoxy resin and composition with only 10 phr PUR. Infrared spectra analysis of the compositions containing PUR revealed the formation of an interpenetrating polymer network structure between the modifier and the polymer matrix

3D braided glass fiber reinforced visible-light-cured resin composites (denoted as G_3D/EEPE) were prepared by impregnation plus light-cured technique, and their tribological properties were studied in this work. It was found that the coefficient of friction and the specific wear rate of the G_3D/EEPE composites decreased with increasing V_f. Beyond a V_f of 32%, however, a slight increase in the specific wear rate of the G_3D/EEPE composites was found. The decreased friction coefficient and increased specific wear rate were observed in the G_3D/EEPE composites with increasing normal load regardless of velocity. The silane coupling treatment effectively improved the wear resistance of the G_3D/EEPE composites. Though the G_3D/EEPE composites showed lower friction coefficient and specific wear rate at lubricated condition than at dry contact, the similar adhesive wear mechanism was observed under two conditions.

High conductive composites were manufactured using single screw extruder melt compound method with carbon black (CB)-filled high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDPE). A low percolation threshold value was achieved from the composites consisting of 2 wt% CB (Printex) with HDPE (HDPE3690). The impact strength of CB/LDPE and CB/LLDPE composites were almost 20 times higher than that of CB/HDPE3690. The tensile modulus and strength of conductive composites increased with the content of CB. Microstructures of conductive composites were analyzed using scanning electron microscope and transmission electron microscope. At the 2 wt% CB content, the CB particles have built a conductive network, which lead to high conductivity.

A uniaxial tension experiment was performed for the thermoplastic AS4/PEEK composite laminate with a circular hole. Ultimately the specimen fractured in the vicinity of the minimum cross section of the laminate. Through micro-observation with the OLYMPUS micro-system, the fracture characters and sub-critical damages were captured. It can be concluded that delamination and matrix cracks occurred prior to final failure of the laminate. Furthermore, a numerical simulation for the notched laminacte under uniaxial tension was implemented with a 3D elastoplasticity model to interpret the damage mechanism of the notched laminate.

In this work, hexadecyltrimethylammonium bromide modified montmorrillonite (OMMT), 3-aminopropyltriethoxysilane-grafted montmorrillonite (-APS-g-MMT), and zeolite were used as thermal stabilizers in PVC compound. The thermal stabilities of PVC were then assessed in terms of decomposition temperatures by thermal gravimetric analysis. X-ray diffractometer (XRD) was used to characterize the d-spacing of MMT as a result of -APS modification. The XRD results suggested that the d-spacing of silicate layers could increase with a chemical grafting of -APS molecules onto MMT. The zeolite was found to be the most effective stabilizer for PVC as compared with OMMT and -APS-g-MMT stabilizers. It was found that the greater the zeolite and -APS-g-MMT loadings in PVC compound, the higher the decomposition temperatures up to 7 phr. No synergic effect was observed on thermal stabilities of PVC by incorporating a mixture of -APS-g-MMT and zeolite stabilizers in PVC compound.

The traditional metallic materials are replaced by some applications for turning process in PA6 and PA66 GF30 polyamides due to excellent properties such as high specific strength and stiffness, wear resistance, dimensional stability, low weight and directional properties. The addition of short fibers to the polyamides improves the properties over the unreinforced polyamides. As a result of these improved properties and potential applications in several fields of engineering, there is a need to understand the machining of unreinforced and reinforced polyamides. Selection of cutting tool and process parameters is important in machining of these composites. This article presents the application of artificial neural network (ANN) modeling to assess the machinability characteristics of unreinforced polyamide (PA6) and reinforced polyamide with 30% of glass fibers (PA66 GF30). The effects of process parameters such as work material, tool material, cutting speed, and feed rate on three aspects of machinability, namely, machining force, power, and specific cutting force have been analyzed through a multilayer feed forward ANN. The input–output patterns required for training are obtained through turning experiments planned as per full factorial design. The model analysis revealed that the minimum machining force results at low feed rate and independent of cutting speed, whereas the power is minimal when both the cutting speed and feed rate are at low levels for PA6 and PA66 GF30 polyamides machining irrespective of the cutting tool. On the other hand, the specific cutting force is minimal at low cutting speed and high feed rate in case of PA6 material, whereas high values of cutting speed and feed rate are essential for minimizing the specific cutting force for PA66 GF30 polyamide machining.

With the aim of improving compatibility between intumescent flame-retardant (IFR) acrylonitrile–butadiene–styrene (ABS) composites, we have prepared a modified intumescent flame-retardant composite (IFRC) powder by compounding the three components of the IFR normally used with TX-10 surfactant/polyacrylate latex. The ABS/IFRC composites were compared with the unfilled ABS by investigating their thermal degradation and combustion behaviors with differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and a cone calorimeter (CONE). The DSC and TGA data showed that the thermal stability of the ABS/IFRC at high temperature could be enhanced and the char residue formation was effectively increased by comparison with the ABS. The CONE results revealed that IFRC was clearly able to change the decomposition behavior of ABS and form a char layer on the surface of the composites, resulting in an efficient reduction of their flammability parameters compared with the ABS, such as the heat release rate, total heat release, rate of smoke release, total smoke release, and so on.

The objective of the present article was to study the thermal degradation behavior of natural fiber polypropylene composites. Composite materials composed of 50% various natural fibers (wood flour, rice hulls, newsprint, and kenaf fibers) and polypropylene were studied using thermogravimetric analysis (TGA), differential thermal analysis (DTA), and differential scanning calorimetry (DSC). The effect of compatibilzer on the thermal stability of the composites was also evaluated. Contributions of components of one composite formulation to thermal degradation were also evaluated. It was found that among natural fibers, rice hulls were the least thermally stable ones in a polypropylene matrix. The compatibilizer slightly reduced thermal stability while enhancing fiber–matrix interaction and fractional crystallinity. The overall thermal degradation profile of the composite materials was found to be a more or less arithmetic average of those of the components.

This article investigates two different production methods and feasibility in practical application of alternative lignocellulosic (LC) polymer composites. In the first method, LC is conditioned in the sodium sulfite solution before the extrusion process. The second method is based on preparing polymer solution using xylene. As experimental results, xylene consumption was found to be over practical limits and it also required simultaneous mixing to homogenize the composite material, which increases overall costs of the system, besides volatile material xylene had cancer-causing affect. The rheological characteristics of the LC composite obtained by the second method has been improved as compared to virgin polyethylene. However, the difficulty experienced in increasing LC percentage and excess inorganic oxides found in the LC's structure were determined as the negative affects of the second method.

Analysis of steady-state creep in a rotating disc made of Al–SiC_p composite has been carried out using isotropic Hoffman yield criterion and the results obtained are compared with those using von Mises yield criterion ignoring difference in yield stresses. The material parameters characterizing difference in yield stresses have been used from experimental results of other studies. The stress and strain rate distributions developed due to rotation have been calculated and compared for both the criteria. It is observed that the stress distribution is not too much affected due to presence of phase specific thermal residual stress. The presence of residual stress has contributed to an increase in the tangential strain rate particularly in the region near the outer radius of the disc, as compared to the tangential strain rate in the disc without residual stress. The radial strain rate, which is compressive, changes significantly due to the presence of residual stress and even becomes tensile in the middle of the disc. It is thus concluded that the presence of residual stress significantly affects the creep in an isotropic rotating disc.

Biphenol monoacrylate (BMA) was applied to be combined with the traditional hindered phenolic-based binary antioxidant system to form the ternary antioxidant system for the purpose of further improving the thermal oxidative stability of polyoxymethylene (POM). The thermal stabilization effect of BMA on POM was studied by the measurements of isothermal and nonisothermal degradation, formaldehyde emission amount, and balance torque. The thermal stability of the stabilized POM under multiple processing and long-term aging was further studied in comparison with the commonly used antioxidant Irganox245. The results showed that the antioxidant BMA can improve the thermal stability of POM effectively through a unique bifunctional stabilizing mechanism, and much low content of BMA-based ternary antioxidant system can reach the same level of thermal stabilization effect on POM as with Irganox245, which can replace Irganox245 to be applied in the production of POM due to its low dosage and low production cost.

Composites of high-density polyethylene (HDPE) with coconut coir as the fiber and stearic acid (SA) as the coupling agent were fabricated by compression molding. Coconut coir in the form of braided fibers and whiskers were used for the study. Incorporation of the coir, buckled the composites and decreased their tensile strength and elongation at break. The extent of buckling and deterioration in the mechanical properties was proportional to the amount of coir loaded as filler. Treatment of the coir with SA as the coupling agent enhanced the mechanical properties and the thermal stability of the composites. It also reduced the extent of buckling and prevented aging of the composites to certain extent in aqueous and strong acidic and alkaline media. Scanning electron micrographs of the fractured samples showed improved adhesion between coir and HDPE matrix upon treatment with SA.

This article addresses the distributions of interlaminar stresses of centrally notched quasi-isotropic APC-2/AS-4 laminate ([0/±45/90]_2s) in tension by finite element method (FEM). Results include the concentration of interlaminar stresses in the vicinity of free boundaries (including hole edge and free sides); The concentration of interlaminar shear stress dominates at interfaces of -45°/+45° and +45°/0°, and the concentration of interlaminar normal stress, which occurs at the 90°/-45° and 0°/90° interfaces. Further analysis demonstrates that the concentration of interlaminar shear stress is more severe as a whole and the highest interlaminar shear stress occurs near the hole edge. The results of digital speckle correlation measurement experiment validate the FEM result.

The oxygen-containing groups such as C–O, C=O, and C(=O)O were introduced onto linear low density polyethylene (LLDPE) chains by ultraviolet irradiation in air. The irradiated LLDPE was used for modifying polyamide 66 (PA66), and PA66/irradiated LLDPE (90/10) blends were prepared. The structure and properties of the PA66/irradiated LLDPE (90/10) blends were investigated by X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, thermogravimetry, the Molau test, and mechanical measurements. Compared with that in PA66/LLDPE (90/10) blends, the irradiated LLDPE in PA66/irradiated LLDPE (90/10) blends remained in an orthorhombic structure, and the face space did not change. But the melting temperature and the crystallinity of irradiated LLDPE and PA66 in PA66/irradiated LLDPE (90/10) blends decreased due to the strong interface interaction between irradiated LLDPE- and PA66-restrained crystallization. The dispersion of irradiated LLDPE and interfacial adhesion between irradiated LLDPE and PA66 in PA66/irradiated LLDPE (90/10) blends were improved. With increasing irradiation time, the tensile and the impact strength of PA66/irradiated LLDPE (90/10) blends first increased and reached a maximum when the irradiation time was 36 h. Compared with that of PA66/LLDPE (90/10) blends, the tensile and the impact strength of PA66/LLDPE irradiated for 36 h (90/10) blends was enhanced by 31% and 160%, respectively.

The process of repair of structures by using bonded composite patch is an effective and economical method to increase the service life of damaged structures. In this study, the finite element method is used to analyze the behavior of a crack repaired by a circular patch by computing the stress intensity factor (SIF) at the crack tip with and without the disbond. The obtained results show that the boron/epoxy 0° fiber perpendicular to the crack, considerably influences the reduction of the SIF with regard to the boron/epoxy 0° fiber oriented in the parallel direction to the crack. Moreover, the increase of the disbond area amplifies the SIF of the repaired crack and the rate of this increase strongly depends on the disbond area. When the disbond is significant between the patch and the plate, it reduces the repair effectiveness and the crack growth under loading becomes important. The disbond growth results in patch separation.

The use of thermoplastic composite materials in aerospace and naval fields has increased due principally to their high performance associated with low specific weight. In order to screen material behavior, the effects of external environments on the mechanical properties during usage must be clearly understood. Environmental factors such as ultraviolet radiation (UV), corrosive fluids, moisture and temperature can limit the applications of composites by deteriorating the mechanical properties over a period of time. In order to characterize composite materials, are commonly used tensile tests. Another test that can be used in order to evaluate the viscoelastic properties of thermoplastic composite materials is free vibration damping. In this work, the viscoelastic properties of polyamide 6.6/carbon fiber laminates were obtained by two types of tests: tensile and free vibration damping tests. Two families of textile polyamide/carbon fiber composites ([±45] and [0/90]) were obtained by hot compression molding. The present studies have been performed to explore relations between the dynamic mechanical properties and the influence of high moisture concentration of this thermoplastic laminate. The results show that the E' decrease with the increase in the exposed time for polyamide/carbon fiber composite specimens and that free vibration damping technique can be used instead of tensile test in order to know the elastic modulus.

In this study the influence of filler particle size (40, 50, and 60 meshes) and coupling agent concentration (0 and 2 wt%) on the composite mechanical properties were studied. Specimens having 30 wt% wood flour of poplar were mixed with polypropylene and polypropylene grafted maleic anhydride (PP-g-MA) as coupling agent. It was found that strength properties of the composites can be improved moderately by adding 2 wt% PP-g-MA. It was also observed that smaller filler particles provide higher tensile modulus than the larger sized filler. Moreover, increase in aspect ratio of the wood particles contributed to the enhancement in the mechanical properties of the composites. The elongation value was not found to have any considerable variation with particle size. The PP-wood flour composites exhibited low impact strength compared to pure PP. In general, Wood flour could be considered as a potential source of low cost, natural fibers for composites.

The tribological performance of PA6 and carbon fiber reinforced polyamide 6 (CF/PA6) under dry sliding condition was examined. Different contents of carbon fibers were employed as reinforcement. All filled and unfilled polyamide 6 composites were tested against CGr15 ball and representative testing was performed. The effects of carbon fiber content on tribological properties of the composites were investigated. The worn surface morphologies of neat PA6 and its composites were examined by scanning electron microscopy and the wear mechanisms were discussed. Moreover, all filled polyamide 6 have superior tribological characteristics to unfilled polyamides 6. The optimum wear reduction was obtained when the content of carbon fiber is 20 vol%.

The melt volume flow rate (MVR) is an important parameter for characterization of flow properties of polymer. The MVR of the polypropylene composites filled with diatomite particles was measured by means of a MVR instrument to investigate the effects of the filler content, particle size and extrusion conditions (temperature 210–230°C, load 5.0–12.5 kg) on the melt flow properties of the composite systems. The results showed that the MVR of the composites increased as a quadratic function with the increase of load, while decreased nonlinearly with the increase of filler particle diameter. The MVR was a linear function of temperature. The MVR decreased quickly when the filler volume fraction (_f) was <5%, and then reduced slightly with an increase of _f. In addition, the melt shear flow obeyed roughly power law under the experimental conditions, and the influence of particle size on the temperature sensitivity of the melt shear viscosity is insignificant at low filler concentration.

A systematic study of effects of concentrations of maleated polypropylene (MAPP), dicumyl peroxide (DCP), Nanoblend concentrate (MB1001) and birch fibers on the mechanical properties of birch-polypropylene (PP) composite was undertaken with the objective to protect or increase the impact strength without losing tensile strength. Using Stagraphic Plus, the Central Composite Design made it possible to determine the optimum concentrations of additives and to maximize both the impact as well as tensile properties to reach values well above that of virgin PP.

Some oxygen-containing groups such as C–O and C=O were introduced onto the molecular chains of polypropylene (PP) by ultraviolet irradiation at different light intensities in air. The rate of introducing oxygen-containing groups was increased with increasing light intensity. After irradiating at different light intensities, there was no gel formation in PP. The crystal shape of irradiated PP at different light intensities kept unchanged, which was still monoclinic crystal, but its melting temperature decreased and the crystallinity increased, and meanwhile their variation extent was increased with increasing light intensity. The melt flow rate and hydrophilicity of irradiated PP at higher light intensity were higher than those of PP irradiated at lower light intensity. A little of irradiated PP at different light intensities was added into PP/CaCO₃ composite and the PP/CaCO₃ composite compatibilized by the irradiated PP was obtained. Compared with those of PP/CaCO₃ composite, the dispersion, interfacial interaction, and mechanical properties of the compatibilized PP/CaCO₃ composite were improved. The mechanical properties of PP/CaCO₃ composite added with PP irradiated for 40 min at lower light intensity and PP irradiated for 30 min at higher light intensity reached a maximum value.

Formation of nanosized mixed semiconductor Pb_xCd_1-xS in situ into PEO–polymer electrolyte matrix at room temperature is reported. The disperse phase was identified by X-ray diffraction analysis. Optical microscopy shows the increase in amorphicity with dispersal of semiconductor while scanning electron microscope/transmission electron microscope affirmed the formation of nanoparticulates with various sizes. The size distribution was further supported by Ultraviolet/Visible absorption of the colloid. The detailed electrical characterizations show that the dispersed Pb_xCd_1-xS introduced a small (≤13%) electronic conductivity into pure ion conducting PEO:NH₄I polymer electrolyte matrix.

A novel copolymer of -phenylethenylphosphonic acid and styrene was successfully synthesized and used to prepare surface-modified magnesium hydroxide (MH). Flame-retardant polypropylene composites were fabricated by filling the above MH. The combustibility, mechanical properties, and thermal behaviors of the composites were characterized. The results demonstrate that the above properties are improved with the amount of modifier and the phosphonic acid group contents on the main chain of the copolymer. Through the microstructure and the fracture surface morphology of the composites analyzed by transmission electron microscope and scanning electron microscope, the above improvements are mostly attributed to the good dispersion of surface-modified filler and the strong adhesion between the filler and matrix.

This study investigates the 3D stress state of an adhesively bonded double containment cantilever joint with a functionally graded plate under a bending load. The mechanical properties of the through-thickness graded region between a ceramic (Al₂O₃) top layer and a metal (Ni) bottom layer were defined based on a power law distribution and modeled with a layered 3D finite element. The peak adhesive stresses occur around the support corners inside the adhesive fillets at the adhesive free edges. The von Mises stress increases uniformly from the plate half-thickness to both the ceramic and metal layers and becomes peak in the ceramic layer, and increases from the adhesive-metal interface to the adhesive-support interface through the adhesive thickness at the adhesive free edge. Both through-thickness adhesive and plate stress profiles and levels become similar after 20 layers. A ceramic-rich material composition results in similar smoother through-thickness stress profiles and reduces considerably differences between the peak stresses in the ceramic and metal layers. In addition, the Artificial Neural Networks combined with the finite element method indicated that the compositional gradient exponent, the support length, and the plate thickness affected considerably the elastic strain energy using whereas the adhesive thickness has minor effect. As the support length decreases the effect of the plate thickness becomes apparent and the support thickness becomes effective as the support length is kept constant. An optimal joint design requires a support length/plate thickness ratio of 25, a support thickness/plate thickness ratio of 3 and a compositional gradient exponent n between 2 and 10.

This work deals with the stochastic free vibration of laminated composite plates subjected to a thermal loading with general boundary conditions by taking into account the randomness in lamina material properties and thermal expansion coefficients. The system equations have been derived based on higher order shear deformation theory incorporating rotary inertia effects. A C ⁰ finite element method is used for treating the random eigenvalue problem. A mean centered first-order perturbation technique is adopted to examine the stochastic characteristics of thermal free vibration response. The results have been compared with those available in the literature and independent Monte Carlo simulation.

Three-dimensional thermo-mechanical stresses in laminated cylindrical panels are theoretically investigated. The cylindrical panels are simply supported at four edges and are subjected to nonuniform thermal and mechanical loadings on the inner and outer surfaces. The theoretical model of this problem is established by using 3D thermo-elastic theory. Analytical solutions of 3D temperature distribution and thermo-mechanical stress fields are derived by using variable separation approach and series solving method. A three-layer laminated cylindrical panel is numerically analyzed by using the present method. All results are graphically presented and briefly discussed.

In order to improve the compatibility between hydrophilic starch granules and hydrophobic poly(lactic acid) (PLA), glycerol was used as plasticizer and citric acid (CA) was used as the additive to enhance the dispersion and the interfacial affinity in thermoplastic starch (TPS)/PLA blend. Water had been recognized as positive component for the properties of TPS, but it also could deteriorate the properties of PLA. So the influence of water on the properties of TPS/PLA blends was investigated through scanning electron microscopy (SEM), rheological thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR), Dynamic mechanical thermal analysis (DMTA) and tensile testing. In the presence of water and CA, the plasticization of starch in TPS/PLA blends could be improved dramatically. At the same time, a homogeneous TPS/PLA blends could be detected by SEM. But high CA and water content decreased the thermal stability of TPS/PLA blend as shown in TGA. In addition, FT-IR spectroscopy proved that CA and water could improve the interaction between TPS and PLA. The tensile testing showed that the maximum tensile strength of TPS/PLA blends could increase to 42 MPa higher than that of pure PLA. DMTA were also studied in this paper.

Some oxygen-containing groups such as C–O and C=O were introduced onto the molecular chains of polypropylene (PP) through ultraviolet irradiation at different environmental temperatures in air. The concentration of the oxygen-containing groups was increased with the increasing environmental temperature after the same ultraviolet irradiation time. After irradiation at different environmental temperatures, there was no gel formed in PP. The crystal shape of irradiated PP kept unchanged, which was still monoclinic crystal. After the same ultraviolet irradiation time, the melt temperature of the irradiated PP decreased and its crystallinity was increased with the increasing environmental temperature. Compared with those of PP, the melt flow rate and hydrophilicity of the irradiated PP was improved, and their variation ranges was expanded with the increasing environmental temperature. The mechanical properties of PP/CaCO₃ composite compatibilized by irradiated PP at different environmental temperatures were enhanced compared with those of PP/CaCO₃ composite. Besides, the compatibilization of PP (irradiated at high environmental temperature for short time) was equivalent with that of PP (irradiated at low environmental temperature for long time).

This paper reports the results of the analysis of carbon fiber/polyamide 6 (C/PA6) composites on micro- and macroscale. Two different hybrid yarns, side-by-side (SBS) and fiber-impregnated (FIT) yarns have been studied. To provide information about the role of the surface sizing on the overall properties of the composites, differently sized carbon fibers (C-Hercules and C-Torayca) are used for preparation of model and macrocomposites based on SBS yarns. Consolidation of macrocomposites is performed based on previously optimized processing parameters (250°C, 3 MPa, 30 min) obtained by DSC measurements of model composites. The properties of the composites are studied by tensile test, DMTA, DSC, and TGA. The homogeneity of the fiber distribution and surface fracture after tensile test are analyzed by SEM. The comparison of the results of the same type composites with differently sized carbon fibers has shown improvement of the mechanical properties (~30%) due to the proper fiber/matrix interface (E_CH/PA6 = 66.7 MPa, E_CT/PA6 = 44.5 MPa). Thermal analysis of the model and macrocomposites has shown that the crystallization energy conditions are more suitable in composites than in the neat PA6 matrix (t_{i CH/PA6} = 0.87 min, t_{i PA6} = 0.92 min, T_{onset CH/PA6} = 206°C, T_onsetPA6 = 216°C).

Polyetheretherketone (PEEK) composite belongs to a group of high performance thermoplastic polymers and is widely used in structural components. In order to improve mechanical and tribological properties, short fibers are added to unreinforced thermoplastics. Both unreinforced and reinforced PEEK composites find potential applications in manufacturing processes due to high specific properties and hence it is necessary to investigate the machining performance. This paper presents the application of response surface methodology (RSM)-based approach to study the machinability aspects of unreinforced PEEK, reinforced PEEK with 30% of carbon fibers (PEEK CF30) and 30% of glass fibers (PEEK GF30) composites with cemented carbide (K10) tool machining. The experiments are planned as per full factorial design of experiments and second order mathematical models are developed to establish the relationships between cutting conditions (cutting speed and feed rate) and machinability aspects (cutting power and specific cutting force). Analysis of variance is performed to check the adequacy of the models. The parametric analysis indicates that cutting power increases with increase in feed rate while the specific cutting force decreases for both unreinforced and reinforced composites. The results show that K10 tool provides better machinability for PEEK and PEEK CF30 materials as compared to PEEK GF30 work material.