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By Hiroyuki Matsuura, Fumitaka Tsukihashi

"Emission of CO2 gas from steelmaking industry covers more than 12 % of total CO2 emission in Japan. Though many efforts have been made to curtail energy consumption and high energy efficiency of Japanese steel production process has been achieved so far, further reduction of CO2 emission is strongly requested to develop sustainable steel production process and produce “green material”. Recently, authors have proposed the innovative hydrogen production process, in which water vapor is reacted with discharged steelmaking slag to produce hydrogen gas. This reaction can be achieved without any external energy source and operated by huge thermal energy associated with steelmaking slag and FeO or unrecovered Fe droplets that are relatively rich in the slag. In this paper, thermodynamic calculation results with various initial conditions in terms of hydrogen productivity were presented. Laboratory-scale experiments were also conducted to clarify the validity of thermodynamic calculation and the reaction rate in realistic conditions.IntroductionIronmaking and steelmaking process from iron ore through blast furnace and BOF is an essential steel production route for Japanese steel industries to supply high quality steel products in large quantity to society stably. Blast furnace – BOF process requires huge amount of fossil fuels such as mainly coal, resulting the emission of considerable amount of CO2 gas. Since the emission of CO2 gas from steel industries, about 147 Mt (FY2011), accounts for approximately 12 % of domestic CO2 gas emission in Japan (FY2011),[1] it is an urgent issue for steel industries to develop environmental-friendly ironmaking and steelmaking process and reduce CO2 emission. Various kinds of gases and by-products generated from ironmaking and steelmaking processes have been recycled as much as possible at present. Enormous thermal energy is also generated from processes and released to surrounding atmosphere as various forms such as sensible heats of gases, molten steels or by-products, and as heat losses. However, these energies are not utilized before final dissipation to atmosphere. Although various technologies to utilize thermal energy from ironmaking and steelmaking processes have been attempted to develop, practical application of these technologies has not been achieved because the thermal energy is not always useful as an energy source. In steelmaking process by BOF, fluxing agent such as CaO is added during reefing and thus about 100 kg/t-steel of steelmaking slag are generated. Since the steelmaking slag is discharged at temperature range between 1873 and 1923 K after discharge of refined molten steel, it also has large thermal energy. Amount of generated BOF slag is 11.0 Mt/y (FY2012) in Japan.[2] Assuming the amount of steelmaking slag is 10 Mt/y and its average heat capacity from room temperature to 1923 K is 1 kJ/kg·K,[3] unutilized heat is estimated to be 16 PJ/y, which is equal to annual energy consumption of 420 thousand families in Japan.[4]"

Jan 1, 2014

By Laurentiu Nastac

"The importance of investigating solute redistribution during the unidirectional solidification of multi-component alloys is broadly discussed in the literature. A previously developed analytical model that was experimentally validated for Al-Cu, Sn- Bi and Fe-Si dilute binary alloy systems is used in this article to study in detail the solute redistribution, the liquid/solid interface stability based on an extended transient constitutional undercooling criterion and the size of the initial transient region during the unidirectional solidification of Ti-6-4 and Ti-17 alloys. A comparison between Ti-6-4 and Ti-17 alloy systems with respect to interface stability and the size of the initial transient region is also provided. The effective partition coefficients of the alloying elements in these alloys were determined based on specially designed experimental measurements.IntroductionThe importance of investigating solute redistribution during alloy solidification is broadly discussed in the literature [1-5]. One of the relevant applications of this study would be the mathematical modeling of equiaxed and columnar solidification of multicomponent alloys. This includes the instability of the solid/liquid interface. There are several mass and heat transfer processes that involve the calculation of solute redistribution during directional solidification such as industrial directional solidification processes, continuous casting, remelting processes, Czochralski crystal growth technique, floating zone techniques, etc."

Jan 1, 2012

By Hongbo Zhao, Jun Wang, Wenqing Qin, Guanzhou Qiu

Jan 1, 2015

By Zviad Kovziridze

The problems related to the production and research of SiC-Si3N4 composite are presented. The technology of producing the protective casings for tips and thermocouples is developed. Optimum composition charge and technological parameters are defined. The results of casing testing at production plants are presented.

Jan 1, 2006

By Dan Wang, Yuanbo Zhang, Guihong Han, Guanghui Li, Tao Jiang, Yanfang Huang

"Hematite concentrates are characterized by bad high-temperature reactivity and poor balling index, which restrict their large-scale application in the production of oxidized pellets. An organic additive, namely MHA, was authorized and used as binder recently in China. Compared with bentonite, the effects of MHA on compressive strength of hematite pellets at various firing conditions were investigated in this study. Experimental results showed the compressive strengths of preheated pellets with different binders were increased with increasing the preheating temperature and time. The compressive strength of preheated pellets with MHA binder was lower than that of pellets with bentonite, which can be ascribed to the high porosity of pellets with MHA binder. However, the compressive strength of roasted pellets with MHA binder was higher than that of pellets with bentonite. The compressive strength of finished pellets balled with MHA binder 1.0 wt% could meet the operation requirements of grate-kiln process.IntroductionHematite concentrates are characterized by bad high-temperature reactivity and poor balling index, which can lead to the appearance of those problems with increasing the energy consumption, shortening the useful life of equipment, and finally increasing the operation cost of oxidized pellets plants [1-2]. Some investigations have been conducted based on improving the pelletizing technique of hematite concentrates, such as pretreatment of raw materials [3-7], optimization of ore proportioning [8], addition of solid fuels [9-16], and so on. Employing high pressure grinding roller for the treatment of hematite concentrates revealed that the mechanical strength of wet green pellets could be improved. However, the mechanical strength of fired pellets was not improved obviously [7]. Huang, et al., pointed out that the preheating and roasting temperature may be decreased and the compressive strength of fired pellets could be increased by blending a certain proportion of magnetite concentrates with hematite [8]. Nevertheless, there are a variety of magnetite ores different in physical and chemical properties in China, resulting in the instability operation [17]."

Jan 1, 2012

By Zhongliang Tian, Yun Cheng, Yexiang Liu, Ming Jia, Yanqing Lai

"A fundamental electrochemical study of Si ions in Na3AlF6-LiF melts and electrolysis using liquid cathodes was conducted. Cyclic voltammograms (CVs) clearly showed the depolarization of silicon deposition on liquid cathode by forming chemical complexes with the liquid solvent metals. Besides, co-deposition of Al and Si is possible when Si ions are insufficient in the molten salt. Based on the electrochemical results, silicon diffusion into liquid cathode is modelled and evolution of Si activity with concentration is deduced by a mathematic approach. Electrochemical study using liquid metals as working electrodes, can be used as an alternative approach for the acquisition of basic data on alloy behavior. Galvanostatic electrolysis showed that liquid cathodes are appropriate to collect the deposited solid silicon and the highest collection efficiency is almost 85%.IntroductionRecent years have witnessed an increasing demand for solar-grade silicon (Si) by the photovoltaic industry [1-4]. The preparation of high-purity metals through electrolysis and electrorefining offer many advantages such as low cost, low-energy consumption, and environment-friendly process, and thus has been widely used worldwide. From the perspective of electrochemistry [5-7], by utilizing the electronegativity difference between the impurities and Si and controlling the relevant process parameters, it is possible in principle to electrodeposit monatomic Si from a Si4+-containing compound melt. Moreover, because the carbon content of the high-purity Si obtained through electrolysis can be effectively controlled and used as a very ideal raw material in the preparation of electronic-grade and solar-grade Si, the preparation of high-purity Si through electrolysis has received widespread attention [8,9]. Monnier et al. [9] used a graphite electrode to obtain high-purity Si (99.9 %-99.99 %) from Si02/Na3AlF6 system through electrolysis; however, because the Si was precipitated in a solid form and showed poor conductivity, the deposition rate was too slow. Olsen et al. [10] obtained high-purity Si films via electrodeposition in K2SiF6/KF-LiF system by selecting electrode materials with high surface quality (such as Ag and graphite). However, in order to ensure the film quality, the deposition current density must be relatively low (10-50 mA/cm2), resulting in a low current efficiency and low deposition rate, which are not conducive to reducing energy consumption and applying to practical use"

Jan 1, 2014

By W. J. Guay

Scrubbing of simulated copper reverberatory furnace gases containing 1.0 percent sulfur dioxide with the minus 74 ~m fraction of the San Manuel tailings has shown sulfur dioxide removals of almost 100 percent over an effluent pH range of 3.1 to 4.6 and a wide range of liquid to gas ratios with absorptions of 11 to 17 Kg of sulfur dioxide per tonne of minus 74 um slimes. The high reactivity of the tailings slimes with S02 indicates that the reaction rate is not controlled by the slow dissolution of calcium carbonate in sulfurous acid which characterizes scrubbers using ground limestone. The interpretation of these results has been considerably enhanced by wet chemical analysis and emission spectrographic analysis which show that calcium and iron account for about 90 percent of the SO2 absorption with the rest being accounted for by aluminum, magnesium, potassium, and sodium. Mineralogic examination confirms the, chemical and spectrographic analyses showing that the major constituent removed from the slimes is calcium carbonate, with lesser amounts of chlorite and montmorillonite (silicates containing iron, magnesium, aluminum, and calcium) being removed.

Jan 1, 1981

By Yan Wen

For the impurities in the copper smelting waste acid, SO3, Cu, As, Pb, Zn, Re and other elements enter the waste acid and generate a lot of arsenic residue, gypsum and neutralized residue, in which Cu, Zn and Re metals have not been recycled. Cu, Re and As are separated by step-wise vulcanization. The valuable metals of Cu, Zn and Re are recovered by separating zinc through pH adjustment. Calcium injection is conducted for boiler for reducing the amount of SO3. The residues generated in the form of arsenate and hydroxide will be returned together with arsenic filter cake for smelting treatment so as to achieve the purpose of valuable metal recycling and solid waste reduction and harmless treatment.

By Raghavan Srinivasan, Y. V. R. K. Prasad, William G. Frazier, Steve C. Medeiros

"Aerospace gas turbine disks operate in an environment of relatively high stresses caused by centrifugal forces and elevated temperatures. These severe conditions necessitate the need for materials with good high temperature strength and low cycle fatigue resistance. One class of alloys used for this task is the nickel base superalloys, out of which, lN 718 is the most widely used in the aerospace industry [I]. The properties of IN 718 are attributed to the combined effects of the chemistry, heat treatment, and microstructure. The chemistry is tailored not only for solid solution strengthening but also for precipitation hardening developed during heat treatment, which combined with a fine grained microstructure lead to excellent mechanical properties such as low cycle fatigue resistance and elevated temperature strength. The properties of a gas turbine disk are sensitive to the microstructure, in particular the grain size, which is dependent on the processing history. The ability to precisely control the microstructural development during forging is dependent on controlling the process so that the workpiece is deformed within a ""safe"" region where no microstructural damage or flow instabilities occur. The microstructural mechanisms during deformation may themselves vary within the ""safe"" region and it is desirable to determine them within the range of parameters that are commonly used in industrial processing. The objective of this work is to establish a relationship between the grain size and the process control parameters i.e., temperature and strain rate, in the hot working of IN 178.BackgroundIN 718 belongs to a class of nickel-iron base superalloys with a face-centered cubic (FCC) austenitic matrix strengthened by precipitation of ordered intermetallic or carbide precipitates and is a nickel-rich alloy strengthened by ordered body centered tetragonal (BCT) precipitates, Y"". The alloying of nickel and iron results in the formation of the austenitic matrix, y, while the addition of chromium and molybdenum cause solid solution strengthening. Also, alloying with niobium causes precipitation of the metastable hardening constituent Y"" (Ni3(Nb,Ti)). Extended aging treatments in the temperature range 650 °C - 980 °C allow the more stable orthorhombic 8 phase (Ni3Nb) to form. Trace amounts of boron are also added to serve as grain boundary strengtheners for high temperature creep resistance. Hot deformation of IN 718 is performed between the Y"" and 8 solvus temperatures to facilitate recrystallization and to control grain growth. While deformation below the Y"" solvus (""""962°C) produces no change in grain size, deformation above the Y"" solvus but below the 8 solvus will lead to a dynamically recrystallized microstructure. The presence of the 8 precipitates will pin the grain boundaries after recrystallization and restrict grain growth so that a fine grain microstructure is obtained. Deformation above the 8 solvus ("""" 1038°C) will lead to a microstructure which has undergone grain growth during deformation."

Jan 1, 2000

By Dave Tahija

"Many investigations are being performed with the goal of removing carbon dioxide from the atmosphere and permanently storing it in geologically stable settings. At the same time, carbon dioxide in the form of dissolved carbonate is steadily accumulating in the world's oceans. Both carbon dioxide sequestration and oceanic accumulation are constrained by the aqueous thermodynamics of the carbonate system. These constraints are illustrated using the STABCAL computer model to generate potential-pH and aqueous distribution diagrams of seawater in contact with various pressures of carbon dioxide gas. STABCAL diagrams and titration simulations are also used to model some potentially useful cation-carbonate sequestrationsystems.IntroductionAtmospheric carbon dioxide concentrations have risen dramatically in the past couple of centuries and are rising still, primarily as a result of human activities, especially the burning of fossil fuels. Increased atmospheric carbon dioxide concentrations have been implicated as a main cause of global warming but have other effects as well.Rising levels of atmospheric carbon dioxide result in increased concentrations of dissolved carbonate complexes in water, including the oceans. These dissolved carbonates interact with other dissolved substances, altering overall seawater chemistry, most noticeably causing lowered pH levels.Some of these chemical changes are observed directly, for instance the general drop in oceanic pH, [1], while others can be inferred and predicted using thermodynamic modeling. The chemistry of dissolved carbonate in seawater is not especially intricate, as such chemical systems go, but neither is it simple enough to be worked out on the back of an envelope. Interactions between the several simple carbonate species and all the major dissolved cations in seawater should be considered, as well as the effects of competing anions, especially chloride and sulphate, since they are much more abundant than carbonate in seawater."

Jan 1, 2011

By Lei Zhang, Shining Chen, Lina Wang, Pu Liu, Benquan Fu, Jiannyang Hwang

A PFS(polymeric ferric sulfate) coagulation-photocatalytic oxidation technology was used for advanced treatment of coking wastewater from secondary biological treatment. Effects of some key factors on TOC removal rate were investigated, and the results were compared with those of the common photocatalytic oxidation technology under the operating parameters of the photocatalytic oxidation defined. Single factor experimental results showed that TOC removal rate could reach 81%, when optimal operating conditions were as follows: TiO2 loading: 4.0g/L, irradiation time: 4h, initial pH is 5.1and PFS dosage:700mg/L. PFS coagulation and photocatalytic oxidation have synergistic effect, which is meaningful for highly efficient treatment of coking wastewater

Jan 1, 2015

By Junji Shibata

Extraction behavior of Ti(IV) and other metal ions, such as Fe(III), Fe(II), Cu(II), Zn(I1) and Co(I1) from acidic solutions like sulphuric acid and hydrochloric acid was studied in order to recover titanium from the waste solution in Ti02 production. Extractant used was tri-alkyl phosphine oxide whose trade name was Cyanex 923. Then, a study was made of the idea of simulating a countercurrent multistage extraction system, using the results of batch extraction. The simulation was camed out on extraction and saipping behavior for a Ti(1V)-H$O,-Cyanex 923 system. From the simulation result., the optimum operating condition of the system was considered.

Jan 1, 1994

By Mrutyunjay Panigrahi, Takashi Nakamura, Atsushi Iizuka, Etsuro Shibata

"The production of FeTi intermetallic alloys from mixed oxide precursors using direct electrolytic reduction was studied. Fe203 and Ti02 powders were mixed in appropriate molar ratios, pressed into small pellets, and then heat treated at temperatures in the range 1000-1300°C. The pellet heat treated at 1000°C was electrolyzed in molten CaCh at 950°C, using a graphite crucible as the anode and the oxide pellet as the cathode, at a potential of 3.0 V. The products of the electrolytic reduction of (Fe,Ti) oxide were examined by XRD, SEM and EPMA. It was found mat the (Fe,Ti) oxide was reduced progressively from the outside to the inside of the pellet until the metallic state was achieved.IntroductionFast and energy-efficient technologies for materials production are essential for the sustainable development of society, and such development is supported by advanced technologies. Since the introduction of titanium and titanium alloys in the early 1950s, these materials have, in a relatively short time, become major materials for the steel, aerospace, energy, and chemical industries. Its combination of a high strength-to-weight ratio and excellent mechanical properties and corrosion resistance make titanium the best material for many critical applications [1]. Titanium alloys are now used in demanding applications such as static and rotating gas-turbine engine components. Some of the most critical and highly stressed civilian and military airframe parts are made of titanium alloys. The use of titanium has expanded in recent years to include applications in nuclear power plants, oil-refinery heat-exchangers, marine components and medical prostheses.Ferrotitanium is one of the most widespread and effective ferroalloys. It is also a well-known hydrogen-storage material and will be extensively used in the future because hydrogen is emerging as an eco-friendly energy source [2], Ferrotitanium is an alloy consisting of iron and titanium, with a minimum titanium weight content of 20% and a maximum titanium weight content of 75%, and is manufactured by reduction or melting."

Jan 1, 2012

By Huang Chao

The thermodynamics analysis on reducing-matting smelting of sulfide ore of lead, antimony and bismuth which use ferric oxide as sulfur fixed agent is first analyzed. Due to the analysis of reaction mechanism, ferric oxide is first reduced to ferrous oxide, then ferrous oxide produce reducing-matting reaction with sulfide ore and reducing agent as reaction equation: MeS+FeO+CO=Me+FeS+CO2. The reaction thermodynamic calculation shows that the reducing-matting reactions of lead sulfide, antimony sulfide, Jamesonite, and bismuth sulfide are feasible, but is infeasible for zinc sulfide. These conclusion provide a feasible method for solve the pollution which produced in the smelting of sulfide ore of lead, antimony and bismuth.

Jan 1, 2006

By H. Fukushima, T. Ohgai, N. Baba

The electrodeposition behavior of Zn and the morphology of the deposited Zn were studied in electrowinning solutions containing polymer additives such as gelatin and polyethylene glycol (PEG). The cathode potential was shifted in a less noble direction and the polarization resistance for Zn deposition increased with increasing concentrations and molecular weights of both gelatin and PEG added to the electrolytic solutions. However, when the molecular weights of these additives exceeded about lxlO4, the cathode was depolarized and the polarization resistance for Zn deposition decreased with increasing molecular weight. The crystal grain size and the (002) orientation of the deposited Zn became smaller when the concentration and molecular weight of the additives increased, and the cathode was polarized.

Jan 1, 2000

By Sergio Sanchez-Segado, Yuan Zhang, Animesh Jha, Ahmad Fahmi Ruzaidi

Niobium and tantalum are considered critical materials because the increasing demand in the energy sector which is reliant on limited abundance of these two metals in minerals. Traditionally, niobium and tantalum mineralsare digested using hydrofluoric acid at moderate temperatures, producing oxy-fluorides which are separated by solvent extraction, involving the use ofhazardous chemicals. The increasing environmental pressures are forcing the industry to search for alternative low carbon processing methods. In this paper alkali roasting based separation and beneficiation, which is not well understood in the literature, is proposed, for which the kinetics and thermodynamic equilibria for the formation of sodium tantalate and niobate with sodium hydroxide are analyzedat the temperature range of 400ºC to 700ºC. The apparent activation energy of formation,changes from 31.0±0.8 to 22.3±1.2 kJ mol-1 and from 23.8±1.2 to110.2±12.8 kJ mol-1, for tantalate and niobate, respectively. The reaction mechanism is examined on the basis of the analysis of reaction products using X-ray powder diffraction (XRPD) and X-ray fluorescence (XRF).

Jan 1, 2015

By Chen Zhang

Polycrystalline Ti-rich NiTi thin films have been deposited from a single NiTi target using a DC magnetron sputtering system. Free standing film was obtained by using a single crystal silicon substrate. Thickness ofthe thin films is controlled at around 12 pm. In this investigation, the effect of deposition temperature on the microstructure and transformation temperatures of the thin films is studied. Influence of post heat treatment temperatures on the properties of the thin films is also investigated. Transformation temperatures of the thin films are determined by differential scanning calorimetry (DSC). The surface microstructure of the thin films is studied using a scanning electron microscope (SEM), and the crystallinity is determined using x-ray diffractometry. It is found that the thin film deposited on a hot substrate is crystalline even when the substrate temperature is as low as 300°C, while the normal crystallization temperature for an amorphous thin film is around 500°C. The microstructure of the film deposited on a hot substrate shows a very fine grain size. The grain size increases with increasing substrate temperature during deposition. The effect of post deposition heat treatment on grain size is minimal.

Jan 1, 1999

By A. M. Alfantazi, M. Boissoneault, D. B. Dreisinger, J. Synnott

"The effects of five commercially available foaming reagents (range of 0 to 25 ppm) namely Dowfroth 250, Saponin, Yucca, Licorice and Meta-Para Cresol on acid mist control, current efficiency, polarization behavior, and deposit morphology and orientation were investigated. The deposition was carried out using a bench scale electrolysis apparatus (cell volume 3L) at 500 Nm-2 and 38°C for 3 hours from Kidd Creek zinc electrolyte. The acid mist control capability of the various reagents was studied and compared by characterizing the foam layer generated during actual electrowinning conditions and by direct quantitative measurements of acid mist levels on top of the electrowinning cells. Within the range considered, the addition of these reagents reduced the current efficiency, refined the grain size of the deposit, and changed to preferred orientation of most of the deposits. Among the reagents tested, acid mist measurements indicated that Licorice and Dowfroth 250 were the best acid mist suppressant at emissions of 0.30 mglm3 and 031 mg/m3 respectively while Yucca and MPC produced the most mist at 3.0 mg/m3 and 33 mg/m3 emission rates, respectively.IntroductionMost of the world's primary zinc is produced via a combined roast-Ieach-purificationelectrowinning process. Depending on the electrolysis conditions, several additives may be added to the electrolyte. Some (e.g. glue, antimony, sodium carbonate) are added to mainly counteract the detrimental effects caused by impurities while others (e.g. licorice, Saponin) are used as foaming reagents to prevent excessive acid mist formation. Acid mist emission is a problem in many electrolysis operations because it corrodes the equipment and is a health hazard to the workers in the tankhouse as well as it pollutes the environment. Due to recent trends towards more environmental protection and more stringent in-plant hygiene, there is an increasing need to minimize these aerosols. In order to eliminate or minimize these aerosols foaming agents are usually added to the electrolyte to produce a foam layer on top of the electrolyte, thus trapping most of the mist. The ideal foaming agent would trap all of the mist and would not interfere with the electrowinning process. It is also evident that the reagent toxicology, cost and availability are important factors that need to be considered.Review of the available literature clearly indicated that very little work has been done in the past on the subject of acid mist control in electrowinning operations particularly in the area of foaming and anti-misting properties of surfactants. Two papers [1,2] have reviewed briefly the existing technologies for acid mist control. Recently, most of the work in this area has focused on the development of special mechanical devices that could be attached to the electrodes and control the mist generation at the source before it is emitted to the cellhouse [2-5]. On the other hand, extensive body of literature exists that deals with the effects of anti-misting reagents on the electrowinning aspects [6-7]."

Jan 1, 1997

By Laurentiu Nastac

"Two advanced control solidification technologies were studied in this article to improve the quality of the cast ingots as well as to control the solidification structure evolution during the plasma arc melting (PAM) processing of Ti-6-4 ingots: (i) electromagnetic stirring (EMS), and (ii) ultrasonic treatment (UST). The developed EMS modeling approach is based on the numerical solution of Maxwell's equations, fluid flow, and heat transfer equations, and mesoscopic modeling of the grain structure. The UST analysis tool is capable to model acoustic streaming and cavitation. It is used in this work to study ingot solidification under the presence of ultrasound. Predictions of the macrostructure, GET formation and primary dendrite arm spacing for PAM Ti-6-4 ingots processed with and without EMS or UST were discussed.1. IntroductionTitanium (Ti) alloys are melted, refined and cast into ingots through plasma arc cold hearth melting (PAM), electron beam cold hearth melting (EBM) and vacuum arc remelting (VAR) for jet engine applications. Process modeling has become a viable tool to optimize the PAM, EBM, and VAR processes. A comprehensive modeling approach to simulate ingot solidification phenomena in primary melting and secondary remelting processes of Ti alloys would include models for macroscopic mass transfer, heat transfer, fluid flow, acoustic, electromagnetic and species transport. The approach should also include microscopic models to predict the evolution of grain structure in solidifying ingots in conjunction with electromagnetic stirring (EMS) and ultrasonic stirring (UST)."

Jan 1, 2012

By Sergio N. Monteiro

Lignocellulosic fibers obtained from plants like cotton, flax, hemp, sisal, jute and many others are natural materials used, since long time, in basic items such as textile, baskets, roofing and carpets. These traditional natural fibers as well as some new ones are nowadays replacing synthetic fibers as composite reinforcement owing to environmental advantages. The heterogeneous characteristic of lignocellulosic fibers is, however, a limitation for application in composites. The buriti fiber, extracted from a tropical plant tree, is recently being investigated as a possible reinforcement for polymeric matrix composites but no complete information exists regarding its mechanical behavior. The objective of this work was then to carry out a statistical analysis on the mechanical properties? uniformity of buriti fibers. By precise dimensional measurements in association with tensile tests, it was found that the mechanical properties depend on the range of the fibers? dimension.

Jan 1, 2009