bluuebunny/crossref_metadata_2025 huggingface dataset:
The Influence of Yttrium Rich Intermetallic Phases and Heat Treatment on the Microstructure, Hardness and Wear Properties of Al-15%Mg2Si Composite
Authors: Jafari Nodooshan H.R. , Emamy Masoud , Nemati N. , Bahrami A.
Published: February 2011

This study was undertaken to investigate the effect of different concentrations of Yttrium (0.1, 0.3, 0.5, 1.0 wt.%) and heat treatment on the microstructure, hardness and wear resistance of an in-situ cast composite (Al-15%Mg2Si ). The microstructural study of the composite before and after solution and ageing showed both primary and secondary Mg2Si phases in all specimens and intermetallics containing Y (Al2Y) were visible after Solution at 520 °C for 4 hours. Hardness measurement demonstrates that the addition of Y increases the hardness gradually but a reduction in the hardness of heat treated specimen’s occurs with the addition of Y ( 0.5%Y).Wear tests were performed using a pin on disk apparatus. The MMCs were rubbed against a carbon steel pin under a load of 10 and 20 N at a sliding velocity of 0.1 ms−1; track length of 1500 m. The degree of improvement in dry sliding wear resistance brought about by Y addition is strongly dependent on the formation of Yttrium rich intermetallic phases as well as heat treatment influence and the wear behavior determined through the precise measurement of weight loss of the samples and wear rates. Worn surfaces were analyzed by scanning electron microscopy (SEM).
Influence of Iron Oxide Nano Particles on Electrospun Poly (Vinylidene Fluride)-Based Carbon Nanofibers on Hydrogen Storage
Authors: Shahgaldi Samaneh , Yaakob Zahira , Mat Jali Norazrina , Khadem Dariush Jafar , Wan Daud Wan Ramli , Majlan Edy Herianto
Published: February 2011

Electrospun Poly (vinylidene fluoride) (PVdF) fine fiber of 100-300 nm in diameter in ribbon shape was synthesized through the electrospinning process via sol-gel. In order to synthesize infusible nanofibers all processing of dehydrofluorination and carbonization was investigated. Iron nanoparticles was doped with PVDF nanofibers in order to be effective in surface area, and porosity to increase the hydrogen storage. The composition, morphology, structure and surface area of PVDF/Iron Oxide nanofibers were investigated by thermo gravimetric analysis (TGA) to determinate the temperature of possible decomposition and crystallinity, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Micromeritics (ASAP2020) used to study the textural properties of the sample, like surface area, total pore volume, and micro pore volume. The result shows that the PVDF without dehydrofluorination treatment for infusibility become melt at around 160 °C. By adding the iron oxide nanoparticles as a catalyst it can improve the characteristic of the carbon fiber for hydrogen storage. In best of our knowledge, PVDF doping with iron oxide investigated for first time.
Nano-Alumina and Radiation Effect on the Mechanical Properties of High Density Polyethylene/Hydroxy Apatite Composite
Authors: Akmil N. , Abdullah Luqman Chuah , Ahmad M. , Zaman Dahlan Khairul Mohd.
Published: February 2011

The effect of nano-alumina and radiation on the mechanical properties of high density polyethylene hydroxyl apatite composite was investigated. The study showed that nano alumina as filler in the composite enhanced the strength of the polymer matrix and hence improved the mechanical properties of the composite. The study also showed that the mechanical properties of the composite depended on doses of nano alumina used and radiation dose of gamma ray. The maximum radiation dose used in this experiment 100 KGy is the best dose for the composite that enhances the tensile strength, impact, modulus and flexural strength. The interface behavior and strengthening mechanisms are discussed.
Processing and Characterization of Palm Fiber-Polypropylene Composites
Authors: Kahraman Ramazan , Abbasi Sarfraz , Abu-Sharkh Basel
Published: February 2011

Composites of palm fiber and polypropylene were compounded using a mixing device at various temperatures, mixing times, and mixing intensities. Two mixing options were utilized. Either the mixing device was mounted with a mixer or a single screw extruder. The composites were subsequently injection molded into standard tensile specimens for mechanical characterization. Tests were performed to determine the effects of processing parameters such as the mixing and molding temperatures, mixing speed, and mixing time on the mechanical performance of the palm-polypropylene composite. The optimum processing conditions for the mixer were determined to be: Mixing Speed = 50 rpm, Mixing Time = 8 min, and Processing Temperature = 200°C. Optimum extruder conditions, on the other hand, were determined as 40 rpm extruder screw speed and processing temperatures of Zone 1=195°C, Zone 2=200°C, Zone 3=205°C, and Nozzle 210°C. Use of the extruder resulted in higher composite strength with much shorter processing time. Further studies are also being conducted to include coupling agents in the processing to improve the interfacial adhesion between the palm fibers and the polypropylene matrix.
Effect of Loading Concentration on the Electrical and Hardness Properties of MWCNT/Epoxy Nanocomposites
Authors: Royan R. Nishata , Sulong Abu Bakar , Sahari Jaafar
Published: February 2011

Carbon nanotubes have excellent mechanical and electrical properties, and are also a good reinforcement material for composites than conventional materials. The matrix used in this study was epoxy and reinforcement filler in multi-walled carbon nanotubes (MWCNTs). The different MWCNTs loading concentrations (0 ~ 10 wt. %) were added into the epoxy resin. The dispersion of MWCNTs in epoxy resin was conducted using high speed mixer through mechanical shearing mechanism. The mixture of epoxy/MWNTs suspension was poured into the mold and compression molding was conducted for fabrication of MWCNTs/epoxy nanocomposites. The electrical conductivity of nanocomposite by variation of CNTs concentration was measured by the four point probe. Dispersion state of CNTs in epoxy matrix was observed on fractured surface by scanning electron microscopic. Hardness of the composite was tested using the Dinamic Ultra Micro Hardness machine. Non conductive epoxy polymer becomes conductor as addition of CNTs.. Electrical conductivity of nanocomposite plates increased with increasing CNTs concentration. Agglomerations of CNTs were observed on fractured surfaces. This phenomenon due to CNTs which used in this study was at as produced state where no modification is being done on it. Long and entanglement of individual CNTs easily lead to agglomerations. Van de Wall’s force interactions between CNTs also contribute to the agglomerations of CNTs. Hardness of the composite increases with the CNTs loading concentrations until it reaches a maximum peak at the composition of 5wt% of CNTs but the hardness decreases rapidly with loading greater than 5wt% of CNTs.
Fabrication of Porous LSCF-SDC Carbonates Composite Cathode for Solid Oxide Fuel Cell (SOFC) Applications
Authors: Jarot Raharjo , Muchtar Andanastuti , Wan Daud Wan Ramli , Muhamad Norhamidi , Majlan Edy Herianto
Published: February 2011

Composite cathodes made of perovskite La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) and SDC carbonates (SDC-(Li/Na)2CO3) were investigated in relation to their structure, morphology, thermal expansion coefficient and porosity. As a first step, the LSCF powder was prepared by sol-gel technique. This was followed by the preparation of the LSCF-SDC carbonates composite cathode by mixing the LSCF with SDC-(Li/Na)2CO3 electrolyte via solid state reaction in various compositions, i.e. 30, 40 and 50 wt.%, namely 70LSCF-30SDC7030, 60LSCF-40SDC7030 and 50LSCF-50SDC7030, respectively. The powder mixtures were then calcined at 680oC. The resultant powder was fine with surface area of about 3.39-7.42 m2/g and particle size of 0.56-0.66µm. The powder consists of two distinct phases, i.e. LSCF and SDC-(Li/Na)2CO3 as confirmed with x-ray diffraction. The microstructures were observed under scanning electron microscopy (SEM). Increasing the amount of the SDC-(Li/Na)2CO3 electrolyte in the composite cathode was found to bring the thermal expansion of the cathode closer to that of the electrolyte. The cathode pellets were later compacted at different pressures (27, 32 and 37 MPa) and sintered at 600oC. The optimum porosity (20.99-24.98%) was achieved for samples with SDC-(Li/Na)2CO3 content of 30-50% sintered at 600oC and cold pressed at 37 MPa.
Cotton-Epoxy Composites: Development and Mechanical Characterization
Authors: Gohil Piyush P. , Shaikh A.A.
Published: February 2011

Composites are becoming essential part of today’s material because they offer advantages such as low weight, corrosion resistance, high fatigue strength; faster assembly etc. composites are generating curiosity and interest all over the worlds. The attempts can be found in literature for composite materials high strength fiber and also natural fiber like jute, flax and sisal natural fibers provides data but there is need of experimental data availability for unidirectional natural fiber composite with seldom natural fiber like cotton, palm leaf etc., it can provide a feasible range of alternative materials to suitable conventional material. It was decided to carry out the systematic experimental study for the effect of volume fraction of reinforcement on longitudinal strength as well as Modulus of Elasticity (MOE) using developed mould-punch set up and testing aids. The testing is carried out as per ASTM D3039/3039M-08. The comparative assessment of obtained experimental results with literature is also carried out, which forms an important constituent of present work. It is also observed through SEM images and theoretical investigations that interface/interphase plays and important role in natural fiber composite.
Measurements of Interface Fracture Strength between Fiber-Reinforced Composite Laminates and Thin Surface Films Using the Blister Test
Authors: Heitzmann Michael , Hou Meng , Veidt Martin , Paton Rowan
Published: February 2011

The blister test is a promising test method to determine the interface fracture toughness of thin films adhering to rigid fibre reinforced plastics. In this paper nonlinear finite element analysis is used to determine a suitable layout for both the shaft loaded and the pressurised blister test. On the example of a PET film adhering to a quasi-isotropic fibre reinforced plastic, it is shown that energy release rates in a range of 0-1500N/m can be obtained for a 0.5mm thick film if test parameters are carefully selected. The two main causes for deviations of the analytic solution from the FEA results is attributed to infringement of the membrane limit condition and plastic deformation in the film.
Comparison on Rheology Properties of Polypropylene and Polyethylene as Binder System with Stainless Steel 316L for Metal Injection Moding
Authors: Abdullah Mohd Fazuri , Sulong Abu Bakar , Muhamad Norhamidi , Chua Abdullah Muhammad Ilman Hakimi , Yahya Nor Hamdan Nor
Published: February 2011

The comparison of binder system between PP/ palm stearin and PE/ palm stearin both mixed with palm stearin were studied based on the rheological properties to (MIM) process. The microstructure of distribution and dispersion studied using scanning electron microscope (SEM) to observe the pattern of the attached binder with stainless steel powder. The types of binder system used were palm stearin with Polypropylene (PP) and Polyethylene (PE). The powder loading for stainless steel 316L with average size of 20µm used was determined at 66 vol %. The palm stearin was the main significant factor for both viscosity and sensitivity of the feedstock behavior. Less content of palm stearin reduce the viscosity of the feedstock in the range of 100-10000 Pa.s and less influence on changing towards temperature and pressure. As the percentage of addition of palm stearin increase, the feedstock becomes less viscous with high sensitivity. PP and PE feedstock shows dilatant and pseudoplastic flow behavior respectively. PE homogenously coated each of stainless during morphology observation. Meanwhile poor distribution of PP can be observed from SEM observation at 1000x magnification.
Optimizing the Curing Process of Epoxy-Clay Nanocomposites
Authors: Al-Qadhi M. , Merah Necar , Mezghani K.
Published: February 2011

Epoxy resin is one of the most applied thermoset polymers as a matrix for Glass Fiber Reinforced Pipes (GFRP). Curing process of epoxy resin is important for the integrity of the GFRP. The present work has been conducted to determine the proper pre-curing and post-curing temperatures and duration to develop epoxy-clay nanocomposite. During this study a differential scanning calorimeter (DSC) was used to determine the glass transition temperature and hence the degree of curing. Several samples of epoxy were prepared at different pre-curing and post-curing temperatures and durations. Pre-curing temperatures ranging from 80 to 150°C and post-curing temperatures ranging from 150 to 200°C were studied. The results show that the optimum pre-curing and post-curing temperatures are 100 and 170°C, respectively. Regarding the effect of curing duration, several specimens were prepared at the same pre-curing and post-curing temperatures with different curing durations of 1, 2, and 3 hours. It was observed that beyond one hour curing, the changes in the Tg and the degree of crosslinking were negligible. Using these optimum conditions samples of epoxy-clay nanocomposites were prepared using ultrasonication. The results showed that the addition of nonoclay to epoxy resulted in a reduction of the Tg.
Large Deflection Behavior of Composite Laminated Plates under End-Shortening and Normal Pressure Loading Using a Semi-Energy Finite Strip Method
Authors: Ovesy Hamid Reza , Sadr-Lahidjani Mohammad Homayoun , Hajikazemi Mohammad , Assaee Hassan
Published: February 2011

In this paper, the application of previously the semi energy finite strip method (FSM) for the non-linear post-buckling analysis of rectangular anti-symmetric laminates is extended to include the effects of normal pressure loading in addition to the progressive end-shortening. One of the main advantages of the semi-energy FSM is that it is based on the closed form solution of von Kármán’s compatibility equation. The developed finite strip method is applied to analyze the large deflection behavior of anti-symmetric angle ply composite laminated plates with simply supported boundary conditions at its loaded ends. To validate the results, they are compared with those obtained from finite element method (FEM) of analysis.
The Effect of Silane Treatment on Processing Characteristic and Swelling Behavior of Polypropylene/Recycled Acrylonitrile Butadiene Rubber/Rice Husk Powder Composites
Authors: Ragunathan Santiagoo , Hanafi Ismail , Kamarudin Hussin
Published: February 2011

The effect of silane treatment on processing characteristic and swelling behavior of recycled acrylonitrile butadiene rubber (NBRr)/polypropylene (PP)/rice husk powder (RHP) composites has been studied. Polypropylene/recycled acrylonitrile butadiene rubber/rice husk powder (PP/NBRr/RHP) composite were prepared by melt mixing technique at 180º C for 9 minutes and 50rpm rotor speed using an internal mixer. Five different composites compositions (70/30/0, 7030/5, 70/30/10, 70/30/15 and 70/30/30), with silane treated RHP (treated) and without silane treatment RHP (untreated) was studied. The specimens were analyzed for swelling behavior with ASTM oil No.3 and processing torque of composites was obtained during composite preparation. The results showed that swelling percentage for both composites increased with NBRr content. However the treated composites exhibited lower swelling characteristics. Processing torque of both composites also showed higher torque reading with increasing NBRr content. However the treated composite with silane exhibited much higher torque value for similar composition composites. Better interaction between RHP filler and PP/NBRr matrixs was obtained with treated composites.
Buckling and Post-Buckling Improvements of Laminated Composite Plates Using Finite Element Method
Authors: Rasid Zainudin A. , Amran Ayob , Zahari Rizal , Mustapha Faizal , Majid D.L. , Varatharajoo Renuganth
Published: February 2011

The improvements of buckling and post-buckling behaviours of laminated composite plates were done by changing the composite related parameters such as the level of anisotropy, thickness to width ratio and boundary condition. In recent years, shape memory alloy has been used to achieve such improvements. A study is conducted on the buckling and post-buckling improvements of composite plates due to the combined effects of composite and shape memory alloy related parameters. Shape memory alloy wires are embedded within laminated composite plates and the amount of recovery stress induced by the shape memory wires is predicted using the Brinson’s model. A geometric non-linear finite element method is used to model the buckling and post-buckling behaviours of shape memory alloy composite plates and source codes are developed to solve the model. It is found that significant improvements in buckling and post-buckling behaviours of composite plates can be attained by combining the effect of shape memory alloy and composite related parameters.
Assessment of Strength Properties of Biocomposite from Oil Palm Frond
Authors: Fauzi Faizah Muhamad , Muhammed Suhaimi
Published: February 2011

Shortage of solid wood supply as the main raw material for the wood-based industries is cute problem faced by the world wide wood industry. Agricultural residues especially from oil palm plantation are abundantly and is therefore hoped to solve the above problem. In this context, this study would like to venture into the utilization of oil palm frond (OPF) as the potential agricultural residues for the manufacture of biocomposite panel. Raw material (OPF) mixed with the binder urea formaldehyde at three resin levels (8%, 10%, and 12%) to produce board of two density levels (550 kg/m3 and 650 kg/m3). The boards produced were tested for the mechanical strength (MOE & MOR) in accordance with the European Standard (EN 310). The results showed that the MOE values increased as the resin content increased for both board densities. The values are 1755.54 MPa to 2147.44 MPa for 550 kg/m3 and 2351.81 MPa to 2810.34 MPa for 650 kg/m3. Respectively, similar trend of increment was exhibited for the MOR values 12.18 MPa to 14.98 MPa for 550 kg/m3 and 16.62 MPa to 19.90 MPa for 650 kg/m3. In conclusion, the utilization of oil palm frond for the production of strong biocomposite material stands a great potential.
Mechanical and Physical Properties of Cement-Bonded Perticleboard Made from Tea Residues and Hardboards
Authors: Yel Hüsnü , Dönmez Çavdar Ayfer , Kalaycioğlu Hülya
Published: February 2011

The residues of tea factory and waste hardboards are generally incinerated without utilizing their heat performances. The first objective of this study was to manufacture cement bonded particleboard using residues of tea factory (Camellia sinenses L.) and waste hardboards. The second objective was to evaluate modulus of rupture (MOR), modulus of elasticity (MOE), internal bonding strength (IB), water absorption (WA) and thickness swelling (TS) properties of the boards produced. The boards were produced at two density levels of 800 and 1200 kg/m3 and at five lignocellulosic mixture ratios of poplar chips/hardboards/tea residues (1/0/0; 1/1/0; 1/0/1; 0/1/0; 0/0/1, based on weigth). All the boards were produced at lignocellulosic material/cement ratio of 1:2.75 on a weight to weight basis. As cement curing accelerators, Al2(SO4)3 and Na2SiO3 were used at ratios of 1.5% and 3.5%, based on cement weight, respectively. The MOR values ranged from 0.8 to 10.99 MPa and MOE values ranged from 254 to 2979 MPa. The mean values of WA and TS after 24 h of water soaking of the cemen bonded particleboards ranged from 28% to 43.5% and 1.3% to 8.08%, respectively.
Numerical Aspects of Delamination Modeling Using Interface Elements
Authors: Hosseini-Toudeshky Hossein , Jalalvand Meisam , Ghayour Mohammad Hossein
Published: February 2011

In spite of a vast background on cohesive constitutive law and its use for various analyses such as delamination in composite laminates, some numerical aspects of that have been less explored and reported in the literature. The aim of this paper is to study the phenomenon of spurious stress oscillation and also dominant process zone (where damage has its most significant evolution) in delamination modeling. For this purpose, distribution of normal stress and damage parameter of different DCB specimen are analyzed. Distribution of stress around the process zone indicates spurious oscillation just ahead of the delamination tip where damage parameter is zero and no effect of this phenomenon is seen on results of applied load versus opening displacement. Additionally, it is shown that larger values of penalty stiffness lead in smaller length of dominant process zone and very large values of penalty stiffness pushes the distribution of damage parameter to become step-like function. Authors believe that this effect is in fact the main reason of un-converged solution of models with too large penalty values.
Effect of Flame Retardants on Wood Plastic Composites-HDPE Based
Authors: Hamid Mohd Rashid Yusof , Sahrim Ahmad Haji
Published: February 2011

Recently, research on natural fiber reinforced polymer composites has gained importance due to the abundant sources of fibers that can be obtained at very low cost. In this study, wood plastic composite (WPC) materials is made by mixing (compounding) high density polyethylene (HDPE) and (ligno) cellulose fiber, i.e. rice husk reinforced with sawdust have been manufactured using a high volume process using counter rotating twin screw extruder. Different fire retardant agents have been employed in order to improve fire behavior in this study. The flammability and thermal stability of WPC-HDPE based in different compositions have been carried out by fire test method according to ASTM D635-06 and evaluated by thermo gravimetric analysis respectively. The properties of flexural strength and impact strength were also included.
Sintering of Fe-TiC Composite Prepared by Carbothermal Reduction of Hematite and Anatase
Authors: Salihin Hassin Mohd , Samayamutthirian Palaniandy , Hussain Zuhailawati
Published: February 2011

In this study, the formation of Fe-TiC composite through carbothermal reduction of hematite and anatase was investigated with various sintering temperature. Mixture of hematite and anatase powders was milled with graphite for 20 hours in a high energy ball mill in argon atmosphere with composition of Fe-30%volTiC. The as-milled powder was analyzed with X-ray diffraction analysis and the result shows broadening of hematite peaks with disappearance of anatase and graphite peaks due to refinement of powder and diffusion of carbon. The as-milled powder was cold pressed under 200 MPa and sintered in argon atmosphere at various sintering temperature i.e, 1200°C, 1300°C and 1400°C. Higher sintering temperature facilitated reduction of hematite and anatase to produce Fe-TiC composite.
Effect of Fibre Size and Fibre Loading on Tensile Properties of Hybridized Kenaf/PALF Reinforced HDPE Composite
Authors: Aji I.S. , Zainuddin E.S. , Khalina Abdan , Sapuan S.M.
Published: February 2011

Hybridization, especially where only variant natural lignocelluloses are combined, is fast receiving encouraging attention because it offers range of properties that are quite difficult to obtain with a single kind of reinforcement. In this work, tensile strength and modulus of hybridized kenaf/PALF reinforced HDPE composite was examined. Pellets were produced form the mixture of the composite in an internal mixer at 190oC, 40rpm and 25minutes for processing temperature, speed and duration of mixing respectively. The composite sheets with thickness of 1mm produced from pellets were prepared using compression moulding. Then the tensile specimen were prepared and tested using an INSTRON bluehill universal testing machine according to ASTM D638 requirements. All samples were prepared at 1:1 kenaf:PALF ratio; ≤0.25mm and ≤0.5mm fibre length; fiber loading of 10 to 40% were utilized. Linear relationship of tensile modulus was observed with about 26% reduction in tensile strength at 10% fibre loading that subsequently reduced but with a reversal increase at 40% fibre loading. This was attributed to a better supportive load at that fibre content and a better interaction between fibre and matrix. Furthermore, the result also corroborates with the one obtained for the tensile modulus at same fibre loading. The best tensile strength and tensile modulus obtained was 32.43MPa;642.61MPa and 30.01MPa;636.73MPa for 0.25mm and 0.5mm fibre length respectively. Increase in fibre length did not show any significant improvement in tensile strength which may have been coursed by fibre attrition. It is possible to achieve improved mechanical properties if the fibres are given some kind of treatment.
Recent Developments in PA6/PP Nanocomposites
Authors: Azman Hassan , Imran Muhammad , Wahit Mat Uzir , Balakrishnan Harintharavimal
Published: February 2011

An overview of the recent developments in PA6/PP blend nanocomposites is presented in this paper with an emphasis on their mechanical, thermal and morphological properties. The role of organoclay as a reinforcing agent and polyethylene octene (POE) as an elastomer are discussed in detail. The organoclay increases the strength and stiffness while the POE elastomer increases the impact toughness of the nanocomposites. The effects of various parameters such as PA6/PP blend ratio, organoclay loading and the concentration of elastomer on the nanocomposites properties are also examined. The exfoliated state of organoclay platelets along with the fine particle size and uniform dispersion of POE demonstrate the nanocomposite with improved properties. These materials are attracting considerable interest in polymer research community because they exhibit substantial improvement in properties at low filler contents.
Polymer Based Filler Materials as Infill for GFRP Pile Connector
Authors: Sirimanna Chamila Sampath , Islam Md. Mainul , Aravinthan Thiru
Published: February 2011

Recently glass fibre reinforced polymer (GFRP) tubular piles have been developed for civil engineering applications instead of conventional concrete piles. Considering their suitable applications, the new polymer based filling materials are being developed at the University of Southern Queensland as a part of work done for timber pile rehabilitation. This ongoing project aims to replace portion of the deteriorated timber pile by using GFRP piles. Due to good compressive strength, pumpability and workability, the new polymer base materials are to be filled in between GFRP pile and existing timber pile base. An ongoing research program has been initiated to improve fundamental understanding of these materials and to provide the knowledge required for their broad utilization. In this development, sample trial mixes were considered based on several weight percentages of polymer resin, fly ash and sand. Material parameters such as compressive strength, stiffness, shrinkage and gel time were achieved from the experimental investigation. It has been found that most polymer based trial mixed fillers have high compressive strength and considerable plastic region with more than 10% strain. These results imply that the polymer based filling materials are suitable for both compression and tensile loading situations. However, the behaviour of fillers with GFRP pile connector under different loading conditions is yet to be fully understood.
Preparation and Thermal Properties of Cellulose/Layered Silicate Montmorillonite Nanocomposites Prepared via Ionic Liquids
Authors: Shaya Mahmoudian , Mat Uzir Wahit , Yussuf A.A. , Navid Nematzadeh
Published: February 2011

Environmentally friendly nanocomposites comprising of cellulose and montmorillonite (MMT) were prepared via a green solvent, ionic liquid, 1-butyl-3-methylimidazolium chloride (BMIMCl) using solution casting method. The cellulose concentration and MMT content were varied according to predetermine formulation. The regenerated cellulose nanocomposites were characterized using X-ray diffraction (XRD). The thermal and thermal oxidative properties of regenerated cellulose nanocomposites were studied by thermogravimetric analysis (TGA). Mechanical properties of the nanocomposites films were investigated by tensile strength measurements. The intercalation and exfoliation of MMT in the cellulose matrix were confirmed by XRD results. TGA results showed an increment in degradation temperature and char yield for the nanocomposites. Multistep TGA graph was observed for degradation under air. The results indicated that the addition of MMT up to 6 wt% in regenerated cellulose matrix improved the tensile properties.
Effect of Milling Speed on Properties of Fe-NbC Composite Prepared by Mechanical Alloying
Authors: Rasib Siti Zalifah Md , Hussain Zuhailawati
Published: February 2011

Nowadays, mechanical alloy (MA) method has turned up as one of a new and applicable method for metal matrix composite fabrication due to some advantages such as the ability to form nanocrystalline structure with improved properties. In this work, different milling speed of MA process (100, 200, 300 and 400 rpm) was performed on Fe-17.21wt%Nb-2.23wt%C with milling duration of 10 hours. The mixture was pressed and sintered at 1300oC into a pellet form. Investigation by X-ray diffraction, measurement of hardness and density were carried out. High milling speed resulted on crystalline-to-amorphous transition of XRD peaks of Fe and NbC phases. Different level of MA at different speed also produced fine NbC particles and strain hardening which resulted in increase value of hardness. The presence of pores, particularly in the composite with high milling speed, decreased the density of Fe-NbC composite.
A Wavelet-Based Damage Detection Approach for Acousto-Ultrasonic In Situ Monitoring Systems
Authors: Liew Chin Kian , Veidt Martin
Published: February 2011

In this research, an advanced signal processing technique using wavelet analysis has been developed for a guided wave structural health monitoring system. The approach was applied for the detection of delamination in carbon fibre reinforced composites. A monolithic piezoceramic actuator was attached to a laminate plate for wave generation while laser vibrometry was used to facilitate the measurements of the wave response in a sensor network. This database of wave response was then processed using the continuous wavelet transform to obtain the positional frequency content. Transforms between damaged and undamaged states were compared to ascertain the presence of defects by evaluating the total energy of the time-frequency density function. Results show high damage detection indices depending on the location of the sensor and normalisation factor applied while there are positive indications that this methodology can be extended for damage characterisation.
Effect of a Coupling Agent on Mechanical and Biological Properties of Polyetheretherketone/Hydroxyapatite Bioactive Composite for Prosthetic Medical Device
Authors: Rashidi Ahmad Ramli , Mat Uzir Wahit , Abdullah R.A.
Published: February 2011

For many years, research was focused on developing a medical part of human body from polymer as to replace metal. In this study, the aim is to produce a Polyetheretherketone/Hydroxyapatite (PEEK/HA) composite which posses balance mechanical properties and good spreading of bioactive ceramic, hydroxyapatite. The composite consist of 10-30 wt% HA were compounded via nano-single screw extruder and sample for testing were produced by injection molding. Each formulation of HA was treated with (3-Aminopropyl)trimethoxysilanes coupling agent to compare with untreated HA. The result showed that the slight increasing value of Elastic modulus, flexural strength, tensile strength while decreasing flexural modulus for 10 and 20 wt% HA compared to untreated composite. The enhance of bioactivity has been proven with the incorporation of HA into PEEK. SEM-EDX image showed the bulk formation of apatite layers on the composite surface with 30 wt% HA after 3 days immersed in SBF solution. Finally, these composite be capable of being one of the biomedical part seing as the mechanical properties were found to be within the properties of human cortical and cancellous bone.
Characterisation and Properties of Sintered Glass-Ceramics Produced from Recycling Glass by Using Pressure-Less Method
Authors: Ayoob N.F. , Mohd Juoi Jariah , Rosli Zulkifli Mohd , Rosli N.R.
Published: February 2011

The aim of this research is to develop glass ceramic produced from recycling glass. Waste glass (e.g. container and bottles) of soda lime silica (SLS) glasses is utilised as main raw materials for the formulation of glass ceramic batch composition with the addition of ball clay. The ball clay was added in order to favour shaping. The recycled glass powder are then mixed with the ball clay according to the ratio of SLSG to ball clay of 95:5 wt.%, 90:10 wt.% and 85:15 wt.%. Differential Thermal Analyses (DTA) was carried out in order to determine the thermal characteristic glass powder prior to the batch formulation. The glass was then crushed, milled and sieved to < 75µm and mixed with the ball clay before it was pressed to a pellet by pressure-less method. This pressure-less route is conducted as an approach to a simple fabrication route of the glass-ceramic samples. The green samples are then sintered at different temperature. The dense and strong glass ceramic samples were obtaining at 850oC, with holding time of one hour and morphological characterized with X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) analyses. Results shown that glass ceramic samples produced at this optimized sintering profile had high density and microhardness value with low porosity and negligible water absorption. Overall results indicates that glass ceramic samples have good mechanical properties (e.g. microhardness exceeding 700Hv) and physical properties (e.g. water absorption, density, porosity making them attractive to the structural application. These results are also utilised as a comparison to a glass ceramic samples produced via Cold Isostatic Press (CIP) from the same batch composition formulation and sintering profiles for the purpose of optimizing the waste glass utilization.
Development of Novel Polymer Composite Beam Using Ultrasonic Welding Process for Acetabular Cup Prosthesis
Authors: Goharian Amirhossein , Rashidi Ahmad Ramli , Kadir Mohammed Rafiq Abdul , Abdullah R.A. , Wahit Mat Uzir
Published: February 2011

The objective of this study was to prepare a basic contributed model in beam to examine this novel composition supposed to apply for acetabular cup. Injection molding process used to manufacture of the component whereas ultrasonic welding was utilized to joint two components. Molding and welding value parameters were carried out by trial and error process. Strength bonding of two components was evaluated by single cantilever beam (SCB) test. The Interfacial fracture energy attained by single cantilever beam (SCB) test was exceeded over 1800 after 70 mm crack propagation.
Experimental Investigation and Finite Element Analysis of Dynamic Behavior and Damage of Glass/Epoxy Tubular Structures
Authors: Tarfaoui Mostapha , Gning Papa Birame
Published: February 2011

This paper presents finite element analysis (FEA) of static and dynamic tests of thick filament wound glass/epoxy tubes. The first part involves the validation of elastic properties and identification of damage initiation and its development in dynamic tests. The results of FEA of the dynamic tests without damage appeared satisfactory. An impact model, including material property degradation, is used for damage prediction. The simulated damage is compared with that obtained experimentally. The sizes of projected and cumulated surfaces are of the same order of magnitude as in the experimental measurements.
Synthesis of TiO2/Zno Core/Shell Type Nanocomposite via Sol-Gel Method
Authors: Golobostanfard Mohammad Reza , Ebrahimifard Reza , Abdizadeh Hossein
Published: February 2011

TiO2/ZnO Nanocomposite powders with different Zn/Ti ratios were synthesized via sol-gel method. The as prepared and calcined Titania nanopowders were added to the ZnO sols. Also the as prepared and calcined ZnO nanopowders were separately added to the TiO2 sols. However, in the latter case, the nanocomposite never formed due to the high acidity of the sols. After gelation, the powders were dried and calcined at 500°C for 1h. The phase composition, structure, morphology and optoelectrical properties of the powders were characterized by means of X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), UV-Vis photospectroscopy and photoluminescence spectroscopy (PL). The XRD patterns confirm the presence of TiO2 and ZnO crystalline phases in the TiO2 particles/ZnO sol samples. The FESEM micrographs show that TiO2/ZnO nanocomposites heat treated at 500°C were formed with average diameter of about 250nm with 50nm ZnO particles on clusters of 40nm TiO2 particles. It was found that the optoelectronic properties of the nanocomposites were improved according to the UV-Vis and photoluminescence spectroscopy.
Life Cycle Assessment of Particulate Recycled Low Density Polyethylene and Recycled Polypropylene Reinforced with Talc and Fiberglass
Authors: Al-Ma'adeed Mariam , Ozerkan Gozde , Kahraman Ramazan , Rajendran Saravanan , Hodzic Alma
Published: February 2011

Although recycled polymers and reinforced polymer composites have been in use for many years there is little information available on their environmental impacts. The goal of the present study is to analyze the environmental impact of new composite materials obtained from the combination of recycled thermoplastics (polypropylene [PP] and polyethylene [PE]) with mineral fillers like talc and with glass fiber. The environmental impact of these composite materials is compared to the impact of virgin PP and PE. The recycled and virgin materials were compared using life cycle assessment method according to their environmental effects. Within the scope of the study, GaBi software was used for Life Cycle Assessment (LCA) analysis. From cradle-to-grave life cycle inventory studies were performed for 1 kg of each of the thermoplastics. Landfilling was considered as reference scenario and compared with filled recycled plastics. A quantitative impact assessment was performed for four environmental impact categories, global warming (GWP) over a hundred years, human toxicity (HTP), abiotic depletion (ADP) and acidification potential (AP) were taken into consideration during LCA. In the comparison of recycled and virgin polymers, it was seen that recycling has lower environmental effect for different impact assessment methods like acidification potential, abiotic depletion, human toxicity and global warming.
Structure and Properties Investigation of a Magnesium Alloy Processed by Heat Treatment and Laser Surface Treatment
Authors: Dobrzański Leszek Adam , Tański Tomasz , Malara S. , Król M.
Published: February 2011

The goal of this paper is to present the structure and properties of the magnesium cast alloys in as-cast state and after heat treatment. Moreover the purpose of this paper is to extend a complex evaluation of magnesium alloys after laser surface treatment and the new methodology to determine thermal characteristics of magnesium alloy using the novel Universal Metallurgical Simulator and Analyzer Platform (UMSA). The presented results concern X-ray qualitative and quantitative microanalysis as well as qualitative X-ray diffraction method, light and scanning microscope.
The Influence of Thermal Sprayed Coats Chemical Composition on the Microstructure and Properties
Authors: Książek Marzanna , Nejman Ilona H. , Pałka Paweł , Grzelka R.
Published: February 2011

In the present work, the microstructure, phase composition and microhardness of Cr3C2-NiCr, WCCo, and powdered composite NiCrSiBCr10%,Fe2.5%,Si3.1%,Bi2.1%C; NiCrSiBFe5; NiCrSiBCr5; NiCrSiBFe2.5Cr2.5; HVOF coatings applied on the Al-Si substrate have been compared. The coating cross-sections were examined by optical microscopy (OM), scanning electron microscopy (SEM) and electron transmission microscopy (TEM). For hard Cr3C2-NiCr and WC-Co coatings, a total microhardness level of about 860 and 1240 HV, respectively, was obtained. The microhardness of composite coatings was essentially lower and comprised in the range of values between 420 and 540 HV. The lowest level of microhardness showed the NiCrSiBFe2.5Cr2.5 coating. The most refined microstructure was found in Cr3C2 and WC coatings. The mean size of splat granules obtained in Cr3C2-NiCr had the value of about 2.7 m and of 0.5 m in WC-Co. For comparison, the granules obtained in composite coatings had the dimensions of about 30 μm. An Xray diffraction (XRD) revealed the presence of Cr3C2 and WC carbides in Cr3C2-CrNi and WC-Co coatings. In composite coatings, the phases of Cr3Ni5Si2, Ni3Si, FeSi, Fe2B, Cr3Si, BCr as well as other phases were found. The existence of the analyzed phases was additionally confirmed by the selective etching of coating microstructure. The annealing of coatings at 823K resulted in pore disappearance and increased the coating microhardness.
Structural Investigations of Iron-Based Sintered Alloys after Plasma Nitriding
Authors: Karwan-Baczewska Joanna , Dymkowski Tomasz , Sobiecki Jerzy Robert , Bonarski Jan T.
Published: February 2011

Various nitriding methods are applicable, viz.: gas nitriding, nitriding in powders and plasma nitriding which is one the latest nitriding technologies applicable for parts made of constructional and tool steels. A large of motor car products made from iron-based alloying powders has been subjected to plasma nitriding process in order to enhance their surface properties like: hardness and abrasive wear. One of the main problems of chemical heat treatment alloys produced by powder metallurgy technology is their porosity degree. In the experiments Fe-Ni-Cu-Mo and Fe-Mo sintered structural parts modified by boron were made. Boron activates the sintering process which results in their considerable consolidation in the sintering at 1473 K for 60 minutes in the atmosphere of hydrogen. The experiments are related to the production of sintered structural elements based on iron powder - NC 100.24 as well as Astaloy Mo (Fe-Mo) and Distaloy SA (Fe-Ni-Cu-Mo) modified by 0.2 wt%, 0.4 wt% and 0.6 wt% B. Sintered parts were obtained by mixing powders said above, followed by compacting at 600 MPa pressure and sintered at 1473 K during 60 minutes time in hydrogen atmosphere. Selected sintered parts were plasma nitrided at 883 K during 4 hours time. After plasma nitriding microstructure morphology using light microscopy and phase identification by Xray diffraction technique have been made. The influence of structure and phase composition on the surface properties of examined sintered parts modified by boron, after plasma nitriding have been analyzed.
Osteoblast Behaviour on Nanostructured Ti-Bioceramic Composites
Authors: Jurczyk Karolina , Niespodziana Katarzyna , Jurczyk M.U. , Jurczyk Mieczyslaw
Published: February 2011

Ti and Ti-based alloys are preferred materials in the production of implants in both medical and dental applications. One of the methods that allow the change of biological properties of Ti alloys is the modification of their chemical composition and microstructure. In this study, new biocompatible, nanostructured Ti-x vol% SiO2, Ti-x vol% 45S5 Bioglass, and Ti-x vol% HAp (x=0, 3, 10) materials have been developed, manufactured and studied in terms of their biocompatibility. These materials give the possibility of controlling in detail the grain structure and the composition of the alloy and, consequently, the mechanical and biocompatibility performances. Our results of in vitro studies show that these bionanocomposites have excellent biocompatibility and could integrate with bone. After 1st day of incubation cells show good adhesion to the surface of studied samples in the form of filopodia. After 5 days of incubation, the typical monolayer was observed. With regard to microcrystalline Ti it could help to obtain better dental implants with better mechanical properties and corrosion resistance.
Microstructure and Mechanical Properties of Rapidly Solidified Al-Fe-Ni-Mg Alloys
Authors: Kula Anna , Blaz Ludwik , Sugamata Makoto
Published: February 2011

Rapid solidification (RS) combined with following mechanical consolidation of RS powders is considered as a valuable commercial method for the production of a wide range of metallic materials having fine-grained structures. Reported research results for various alloys demonstrate better compositional homogeneity, smaller grain size and relatively fine precipitates distributed homogenously in RS alloys than that for the materials produced by conventional metallurgical processing. The effect of rapid solidification on the microstructure and mechanical properties of selected Al-Fe-Ni-Mg alloys have been investigated. The basic item of the research work was obtaining aluminum PM materials strengthened by highly-dispersed transition metal compounds and aluminum-magnesium solid solution. Rapid solidification (RS) of Al-4Fe-4Ni and Al-4Fe-4Ni-5Mg alloys was performed by means of gas atomizing of the molten alloy and the spray deposition on the rotating water-cooled copper roll. Using typical powder metallurgy (PM) methods, i.e. cold pressing, vacuum degassing and hot extrusion, the RS-flakes were consolidated to the bulk PMmaterials. For comparison purposes, the conventionally cast and hot extruded Al-4Fe-4Ni and Al-4Fe-4Ni-5Mg alloys were studied as well. Mechanical properties of as-extruded materials were examined by compression tests performed at 293 K – 873 K. It was found that relatively high strength of as-extruded PM materials was accompanied by high ductility of samples deformed by hot compression test. Structural observations confirmed beneficial influence of rapid solidification on effective refining of intermetallic compounds, although some inhomogeneity of fine precipitates distribution was observed. Nevertheless, it was considered that an effective increase of the microhardness and strength of tested RS materials mostly result from achieved dispersion of structural components and can be intensified by solid solution hardening due to Mg-addition.
The Influence of Nanocluster Carbon Materials on the Structure and Properties of Polyamide Nanocomposites
Authors: Burya A. , Kuznetsova O. , Konchits A. , Redchuk A.
Published: February 2011

The work examines the structure and properties of nanocomposites based on phenilon C- 2 filled with nanostructured carbon. The influence of filler concentration on tribological properties of the developed composition materials is shown.
Three-Way Shape Memory Composite Actuator
Authors: Tobushi Hisaaki , Hayashi Shunichi , Pieczyska Elzbieta , Date K. , Nishimura Y.
Published: February 2011

The SMC belt composed of two kinds of SMAs and SMP was fabricated and the three-way movement and recovery force in bending were investigated. The results obtained can be summarized as follows. (1) The three-way bending movement was achived during heating and cooling based on the characteristics of the SMA tapes and the SMP sheet. (2) The recovery force increased during heating and decreased during cooling. The recovery force was evaluated by the proposed simple model.