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For a class of complex production process systems obeying the statistical law, which is difficult to control, a new generalized predictive control method has been proposed. Feature variable (not state variable) is used directly, and the dynamics of system is described by the variation of class which pattern belongs to. Then the controller is designed. But only two-dimensional case was studied before by the author. Considering high-dimensional case, this study takes three-dimensional as an example. Based on the running status data collected from sintering process of Anyang iron and steel plant, feature variable is selected and pattern class is divided firstly. Then the prediction model is constructed by the new defined variable. At last, a new generalized predictive controller is designed. The results show that the statistical characteristics of the system can be effectively described, and the parameters in control law are directly identified by the running status data and prediction model. The difficult control problem is solved by this method. [ABSTRACT FROM AUTHOR]

Coal series kaolin (CSK) is used as the raw material to prepare CSK cordierite electronic ceramics. Sintering process is analyzed by a heating microscope. The microstructure of green body, phase transformation, and microstructure evolution during sintering process is elucidated by scanning electron microscope (SEM) and X-ray diffraction (XRD). Comprehensive evaluations of our product are made for physical properties, electrical properties, and coefficient of thermal expansion (CTE), respectively. According to test results of the obtained CSK cordierite ceramic, the sintering temperature range is 1280~1420 °C, synthetic temperature is 1160~1280 °C, densification process is 1360~1420 °C, and large deformations of cordierite ceramic happen above 1420 °C. The optimum performance of the obtained CSK cordierite ceramics is summarized as follows: volume density is 1.81 g·cm3, apparent porosity is 28%, bending strength is 65 MPa, CTE is 1.41 × 10−6 °C−1 (600 °C), and dielectric constant is 4.6 (100 Hz). As a result, this cordierite electronic ceramics from CSK have great potential to do with applications in electric heater supports, such as electric stove, ceramic heater base, and electric heater cooling plate. [ABSTRACT FROM AUTHOR]

Copyright of Basic Sciences Journal of Textile Universities / Fangzhi Gaoxiao Jichu Kexue Xuebao is the property of Basic Sciences Journal of Textile Universities and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The NOx in the exhaust gas emitted from the coke combustion and sintering process has a serious impact on the environment. How to reduce the release of NOx in the combustion of coke has become a major problem to be solved. Adding a certain amount of catalyst to the coke combustion process can not only effectively improve the combustion efficiency of coke but also reduce the NOx emissions. In this paper, CeO2 is used as an inhibitor for coke combustion experiments, micro-sintering experiments and sintering cup experiments, focusing on the effect of CeO2 on NOx emissions during the coke combustion and sintering process. It is found that in the coke combustion reaction the addition of 1 and 2% CeO2 resulted in NOx reduction of 5.6 and 2.5%. The addition of 3% CeO2 resulted in a 2.8% increase in NOx emissions. When the amount of CeO2 added was 2%, the NO reduction rate during the sintering cup test reached 25.3%. At the same time, the addition of 2% CeO2 resulted in little change in the yield of the sinter, and the increase of the drum strength of the sinter. [ABSTRACT FROM AUTHOR]

Crystalline CuCe x Fe 2-x O 4 nanoparticles with different rare earth metal content (x = 0.00, 0.03, 0.05, 0.08 and 0.10) were synthesized using a co-precipitation technique that involves a 600 °C calcination treatment. The newly obtained powders were pressed into pellets and heated up to 950 °C in order to form a compact and less porous material, ideal for dielectric measurements. X-ray investigations revealed a structural modification from typical cubic system to a tetrahedral spinel form, accompanied by Ce3+ cations exclusion and formation of secondary phases. The amount of phases and cations distribution were determined by Rietveld refinement method. A degradation process of cerium doped copper ferrite was proposed based on X-ray analysis and Rietveld refinement. Furthermore, the magnetic behavior of both 600 °C and 950 °C samples was investigated from the hysteresis loops recorded from a vibrating sample magnetometer (VSM) in a ±10 kOe range. Room temperature dielectric values for the 950 °C samples were determined using the parallel-plate capacitor configuration in a frequency range of 10 Hz – 1 MHz. [ABSTRACT FROM AUTHOR]

Aluminum bronze alloy is applied in environments that require materials of high mechanical resistance and wear, such as marine, oil & gas and aerospace ones. This study analyzes the densification of composites based on aluminum bronze with additions of the vanadium (VC) and niobium (NbC) carbides, and the influence of these carbides in the milling efficiency and improvement of the diffusion process between particles to obtain better results for density and porosity. The composites were produced by powder metallurgy from aluminum bronze powders obtained from the mechanical milling process of discarded scraps. The efficiency of the sintering process depends on parameters, such as the time and temperature of sintering, together with the size of the particles obtained from the milling process. This study aimed to obtain and characterize the composites produced by the powder metallurgy route, with NbC and VC addition and to analyze physical properties, such as density and porosity. The powder morphologies, particle sizes and samples sintered were performed by scanning electron microscopy (SEM), X ray diffraction (XRD), laser diffraction analysis and optical microscopy (OM). The results indicate that addition of VC improves the milling efficiency, when compared to NbC addition, since it promotes a greater reduction of the particle size, directly favoring the sintering process. In this case, to achieve similar particle size, twice the milling time was required when NbC was used. The density values achieve ~ 73% of reference material for VC addition and ~ 68% for NbC and porosities varying between 27% and 38%. [ABSTRACT FROM AUTHOR]

Copyright of Science of Sintering is the property of National Library of Serbia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to monitor the combustion condition and improve the product material quality, a digital image acquisition and processing method is adopted in alumina-sintering process. Two digital properties of flame grade and material grade are obtained by image data analyzing and smooth filtering, which provide reliable reference for operational optimization and automatic control of rotary kilns. This image acquisition system improves the operation of kiln effectively and reduces the working intensity and the manufacture cost. [ABSTRACT FROM AUTHOR]

The effect of the sintering temperature on the formation of secondary phases and ferroelectric properties of Bi0.5(Na0.8K0.2)0.5TiO3 ceramics has been studied. Ceramic powders were prepared by the sol-gel method and sintered at different temperatures. Samples were characterized by X-ray diffraction (XRD), Raman microspectroscopy, scanning electron microscopy, impedance spectroscopy and ferroelectric hysteresis loops. Through XRD and Raman results, the perovskite structure was detected, and the formation of secondary phases was registered. As the sintering temperature was increased, the secondary phase composition was modified. Moreover, dielectric properties were influenced by the resulting grain size and the secondary phase amount. [ABSTRACT FROM AUTHOR]

Limitations in the packaging industry require improvements in lead‐based microelectronics, because regulations restricting hazardous substances have ended the use of conventional lead‐based solders. Sintered silver paste presents an alternative method for bonding chips to a substrate because it has low sensitivity to the oxidation, high melting point, and improved thermal and electrical conductivity. Due to the sintering process, however, the silver exhibits a significant pore fraction that substantially reduces the density of the material compared to bulk silver. The traits of the sintered silver pastes are affected by the pore distribution; hence, it can be considered as a significant factor in modelling the behaviour of the whole electronic system under operating conditions. This study defines the influence of the morphology and pore distribution on the response of the silver material. The quality of tomographic images was improved through coding a program in MATLAB®. Finite element software ABAQUS® was employed to evaluate the elastic properties of the material. To validate the model, the results have gone through several studies to determine changes of the material properties. [ABSTRACT FROM AUTHOR]

Laser scanning is one of the methods that can be used for surface treatments of zirconia. Application of the laser to the surface of zirconia has diverse effects, depending on the type of laser. A carbon dioxide (CO2) laser has high irradiation power and can alter the surface properties. This study investigated the surface coating of zirconia as a core material that subsequently coated with a veneering ceramic (v-c) material. This study compared laser scanning and conventional sintering processes. Various properties including surface topography, interface evaluation, phase transformation, elemental compositions, failure mode patterns, and contact angle were examined through X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analyses. Results were confirmed that the bond strength between the v-c and the substrate recorded through laser scanning was higher than that determined through conventional sintering. [ABSTRACT FROM AUTHOR]

Abstract Acrylic acid and its ester derivatives are important chemicals utilized to synthesize numerous end products. Acrylic acid is industrially produced via propylene oxidation. We report in this study a nickel oxide-silica core-shell catalyst (NiO@SiO 2) for acetylene hydroxycarbonylation as an alternative way to synthesize acrylic acid. NiO@SiO 2 catalyst provided the higher turnover frequency and yield than commercial nickel oxide catalyst on acetylene hydroxycarbonylation. The carbon monoxide/acetylene ratio influenced more significantly to initial reaction rate than final acrylic acid yield. The silica shell protected the nickel oxide from sintering during reaction, however, the catalyst was deactivated by coke formation, attributed to acetylene decomposition. Graphical abstract Unlabelled Image Highlights • The NiO@SiO 2 core-shell catalyst provided higher acrylic acid yield and turnover frequency. • The core-shell structure protected the nickel oxide from sintering. • The acrylic acid itself inhibits the catalytic cycle by binding onto the active sites. • Formation of coke by acetylene decomposition leads to deactivation of catalyst. [ABSTRACT FROM AUTHOR]

In this work, vacuum hot pressed Ni-Mn-Sn-In Heusler alloys with different concentration of In (0, 2 and 4 at.%), were investigated. The magneto-structural behaviour and microstructure dependencies on chemical composition and on heat treatment were examined. It was found that the martensite start transformation temperature increases with growing In content and to a lesser extent with increasing temperature of heat treatment. The high energy X-ray synchrotron radiation results, demonstrated that both chemical composition as well as temperature of heat treatment slightly modified the crystal structures of the studied alloys. Microstructural investigation performed by transmission electron microscopy confirmed chemical composition and crystal structure changes in the alloys. [ABSTRACT FROM AUTHOR]

A series of WC-1.0TiC-3.1TaC-4.5Co cemented carbides were prepared by vacuum sintering and Sintering-HIP through traditional powder metallurgy method. Optical microscopy(OM),scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were used to characterize the microstructures. The results show that pores and cobalt-lake can be reduced in cemented carbides by increasing sintering temperature or using Sintering-HIP. The mean size of WC cemented carbide prepared by vacuum sintering process is larger than that prepared by Sintering-HIP. Furthermore, the phenomenon of WC abnormal growth was found in the cemented carbides prepared by Sintering-HIP.

This present work investigates the effects of sintering temperature on densification, mechanical properties and microstructure of Al-based alloy pressed by high-velocity compaction. The green samples were heated under the flow of high pure (99.99 wt%) N2. The heating rate was 4 °C/min before 315 °C. For reducing the residual stress, the samples were isothermally held for one h. Then, the specimens were respectively heated at the rate of 10 °C/min to the temperature between 540 °C and 700 °C, held for one h, and then furnace-cooled to the room temperature. Results indicate that when the sintered temperature was 640 °C, both the sintered density and mechanical properties was optimum. Differential Scanning Calorimetry, X-ray diffraction of sintered samples, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, and Transmission Electron Microscope were used to analyse the microstructure and phases.

Capillary water absorption of materials is a very important factor in the process of pre-treatment of fine-grained materials. Materials that are in a moisturized state capable of forming a firm, compact pellet are, thanks to this particular physical property, suitable for utilisation in sinter charge preparation within the process of sintering iron-ore raw materials. The pelletising ability of coke dust is generally known and coke dust exhibits good pelletisability. From the ecological point of view, an alternative to coke dust is currently biomass, which has a great potential for industrial applications, including use in the agglomeration process. Understanding of how biomass behaves during pre-pelletisation is very important and for the sintering process, it is essential. The purpose of pre-pelletisation of the sinter charge is to achieve its optimal permeability in the sintering process. The experiment described in the article was carried out using wood biomass—oak and pine sawdust, as well as plant biomass—Miscanthus sinensis and Lavandula angustifolia. The evaluation was carried out by applying the capillary water absorption test and the free-fall drop test. As different types of biomass have different chemical compositions, heating capacities, grain morphologies, and chemical and physical properties, the testing was carried out with several types of biomass. The capillary water absorption was examined in terms of different granulometries, and the impact of the type of liquid medium was analysed. It was observed that different types of biomass differ in their ability to absorb liquids. Another finding was that the type of a liquid medium had a significant effect on the pelletising ability of biomass, which was determined by the surface tension and the ability to form liquid bridges between the grains. Research results indicate an excellent pelletising ability of the Miscanthus sinensis grass. The wettability of oak and pine sawdust determines its application in the pelletising process. It may be concluded, based on the research, that Lavandula angustifolia is not a suitable alternative to coke dust due to its low ability to form pellets.

During development of substitute anode materials suitable for solid oxide fuel cell (SOFC), understanding of sintering mechanisms and effects is significant for synthesized porous structures and performance. A molecular dynamics (MD) model is developed and applied in this study for the SOFC anode sintered materials to reveal the sintering condition effects. It is predicted that, for the case of two nanoparticles of electron-conducting La-doped SrTiO3 (LST), the higher the sintering temperature, the faster the aggregation of nanoparticles and the higher the sintering degree. An increase in the nanoparticle size could delay the sintering, process but does not affect the final sintering degree. The MD model is further applied for the case of the multi-nanoparticles containing LST and ion-conducting electrolyte materials of gadolinium-doped ceria (GDC), i.e., the LST-GDC particles. The sintering conditions and effects on the LST-GDC particles are evaluated, in terms of the mean square displacement (MSD) and various structural parameters. Two important thermal properties are also calculated that agree well with the experimental values. The findings obtained from this study are useful to identify the optimized sintering parameters for development of the SOFC electrode materials.

The work deals with examination of the influence of the ratio between iron ore concentrate and iron ore on quality of produced iron ore sinter. One of the possibilities to increase iron content in sinter is the modification of raw materials ratio, when iron ore materials are added into sintering mixture. If the ratio is in favor of iron ore sinter, iron content in resulting sintering mixture will be lower. If the ratio is in favor of iron ore concentrate and recycled materials, which is more finegrained, a proportion of a fraction under 0.5 mm will increase, charge permeability property will be reduced, sintering band performance will decrease and an occurrence of solid particulate matter in product of sintering process will rise. The sintering mixture permeability can be optimized by increase of fuel content in charge or increase of sinter charge moisture. A change in ratio between concentrate and iron ore has been experimentally studied. An influence of sintering mixture grain size composition, a charge grains shape on quality and phase composition on quality of the produced iron sinter has been studied.

Copyright of Journal of Mining & Metallurgy. Section B: Metallurgy is the property of Journal of Mining & Metallurgy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The phase, microstructure and properties of multi-core cermets based on (Ti,W,Ta)CN and TiCN powders were investigated in sintering process. The analyses of X-ray diffraction (XRD) and scanning electron microscope (SEM) indicate that the sintering behavior of the multi-core cermet in sintering process could be divided into three stages: (I) pre-densification stage (the sintering temperature < 1200 °C); (II) rapid densification stage (the sintering temperature between 1200 °C and 1350 °C); (III) final densification stage (the sintering temperature > 1350 °C). Meanwhile, the evolution of η -phase in multi-core cermets was discussed as well. Furthermore, the microstructural and chemical composition of η -phase were studied by transmission electron microscopy (TEM) using X-ray energy dispersive spectrometry (XEDS) and selected area electron diffraction (SAED). The thickness of the rim structure would increase with the rise of sintering temperature, while the mechanical properties of the material would firstly increase and then decrease with the rise of sintering temperature. The highest transverse rupture strength is achieved at 1450 °C, while the highest hardness at 1390 °C. [ABSTRACT FROM AUTHOR]

This paper introduce a tool for a technical economic analysis of value in use of the metallic burden in iron ore sintering process for commercial technical support in a final price negotiations for iron ore. This tool allows doing a comparative analysis of the impact of the chemical and sizing quality of the iron ore fines on the final cost of production, highlighting the main variable cost items. The methodology of calculation of the value in use can be used by both the steelmakers in the acquisition of the ore and the mining, enabling the valuation of the quality items in the productive process of the customer. [ABSTRACT FROM AUTHOR]

Mo 2 BC ceramic has potential application value in structural fields due to its high strength and hardness. However, the microstructures and mechanical properties of ceramics are greatly depended on the sintering process. In this paper, the effect of sintering temperature on microstructures and mechanical properties of Mo 2 BC ceramics has been studied. Mo 2 BC ceramic bulks were fabricated at the temperature varying from 1300 °C to 1600 °C under a pressure of 50 MPa by fast hot-pressing sintering method. It is well confirmed that the sintering temperature can remarkably influence microstructural evolution and mechanical properties. The results presented here provide an optimal sintering process to prepare Mo 2 BC ceramic bulks. It is established that the two-step sintering process is an effective method to refine the microstructures and improve the mechanical properties. Based on the two-step sintering process, the relative density of as-prepared Mo 2 BC ceramic bulk is as high as 98.5 %. Besides, the Vickers hardness, compressive strength, flexural strength and fracture toughness are all evidently improved, of which the values are 20.1 GPa, 4.95 GPa, 511.5 MPa and 4.7 MPa m1/2, respectively. The enhanced mechanical properties are mainly attributed to the refinement strengthening effect and high relative density. • High dense Mo 2 BC ceramic bulks are prepared by a two-step sintering process for the first time. • The grains of Mo 2 BC ceramic are greatly refined. • The compressive strength increases by two times which is as high as 4.95 GPa. • High densification and grain refinement account for the high strength. [ABSTRACT FROM AUTHOR]

• Silver nanoparticles were prepared by a simple, low-cost and environmentally friendly polyol method, and the average particle size of silver nanoparticles was 53.01 nm by optimizing the reaction conditions. • The effects of two sintering processes on the nano-silver particles were investigated. By optimizing the sintering process, the lowest resistivity of the prepared nano-silver conductive film can reach 0.7 × 10−5Ω·m. • The flexible strain sensor prepared by two sintering methods has good cyclic response performance and temperature stability, which can be applied in practice. In this experiment, silver nanoparticles (AgNPs) were prepared by the polyol method, which is simple and low-cost. The AgNPs were characterized by SEM, UV–Vis, and XRD. It was determined that the prepared AgNPs had good morphology and the average particle size was about 53.01 nm. At the same time, the optimum conditions for preparation were determined: The molar ratio of polyvinylpyrrolidone K30 (PVP K-30) to AgNO 3 was 6:1, the reaction time was 40 min, and the reaction temperature was 160 °C. Then the sintering process parameters were discussed. It was determined that when the content of AgNPs was 2.5%, the temperature of high-temperature sintering should reach 250 °C and above, the time should reach 30 min and above, and the lowest resistivity reaches 0.7 × 10−5 Ω·m under high-temperature sintering. In chemical sintering, Cl− replaces the N and O atoms of PVP K-30, induces spontaneous aggregation of Ag, and completes room temperature sintering. It is found that the sintering time needs to reach 30 min or more, and the resistivity is 3.325 × 10−5 Ω·m. Finally, the conductive region is printed by the material deposition system and the strain sensor is prepared by two sintering methods. The experimental test proves that the sensor prepared by high-temperature sintering has good cycle response and stability. The sensor prepared by chemical sintering has a good cycle response, but the repeatability is poor, which is not conducive to long-term high-strength use. The sensor can be applied to the field of flexible electronic products. [ABSTRACT FROM AUTHOR]

Iron-rich sludge produced during textile wastewater treatment has brought serious environmental burden, and usually undergoes incineration disposal without creating added value. In this work, novel adsorbents were fabricated through sintering treatment with dried iron-rich sludge (denoted as B) as precursor, aiming at the deep Sb(V) removal from textile wastewater. Structural characterization confirmed the presence of various iron oxides including α-Fe 2 O 3 and amorphous ferrihydrite in the as-prepared adsorbents. Screening tests indicated that adsorbent obtained after sintering at 400 °C for 2 h (B-400) exhibited a significantly improved maximum adsorption capacity (161.36 mg g−1) as compared to B (51.72 mg g−1). The B-400 possesses lager specific surface area, and more favorable phases for Sb(V) adsorption as compared to B. Satisfying Sb(V) removal efficiency of B-400 is accomplished within a wide pH window ranging from 4 to 10, at varying ionic strengths. The co-existing ions, dyes and surfactants in textile wastewater trigger different degrees of negative impacts on Sb(V) adsorption by B-400, except for Cl− and cetyltrimethylammonium bromide. The Sb(V) adsorption by B-400 is a heterogeneous surface adsorption process, which can be well described by the Freundlich and Elovich models. The possible mechanisms include electrostatic interaction, inner-sphere complexation, and hydrogen bonding. The findings in this study fulfill the 'waste control by waste' strategy by removing Sb(V) from textile wastewater with textile sludge derived adsorbent materials, which achieves the self-recycling of waste during textile wastewater treatment, and contributes to sustainable development goals. [Display omitted] • Self-recycling of waste during textile wastewater treatment is achieved. • Textile sludge is sintered to fabricate novel adsorbents for Sb(V) removal. • Novel adsorbents contain abundant α-Fe 2 O 3 and amorphous ferrihydrite. • Satisfying Sb(V) removal is fulfilled at various pH and ionic strengths. • The co-existing ions, dyes, and surfactants show negative impacts on adsorption. [ABSTRACT FROM AUTHOR]

In this study composition of sinter mixtures used in Polish sinter plants were established. Seven sinter mixtures composition were examined, based on iron-bearing materials, admixtures and fuels. Contents of harmful admixtures were examined according to three kinds of environmental impacts: emissions of SOx, heavy metals, polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/PCDFs).

W artykule przedstawiono wpływ parametrów spiekania na mikrostrukturę i własności mechaniczne spiekanych, niskowęglowych stali manganowo-chromowo-molibdenowych. W pracy wykazano, że własności mechaniczne stali wykonanej na bazie proszku stopowego Astaloy CrL (l,5%Cr, 0,2%Mo, reszta Fe) spiekanej w temperaturze 1250°C w atmosferze 5%H2-95%N2 nie zależą od temperatury odpuszczania, czego nie stwierdzono podczas badań własności wytrzymałościowych tych stali wy- twarzanych w niższej temperaturze spiekania (1120°C). Ponadto, prowadzone badania wykazały, że stale wytworzone na bazie proszku stopowego Astaloy CrM (3%Cr, 0,5%Mo. reszta Fe) po spiekaniu w temperaturze 1250°C w atmosferze powietrza charakteryzowały się porównywalnymi lub wyższymi własnościami mechanicznymi niż stale wykonane na bazie proszku sto- powego Astaloy CrL, wytwarzane w tych samych warunkach. Podczas spiekania w powietrzu zastosowano odłamkowe cząstki żelazomanganu o łącznej masie 52 g, które umieszczano w bezpośrednim sąsiedztwie próbek (całkowita masa próbek 490 g) w stalowej łódce, w celu redukcji tlenków. Jak wykazały badania, dodatek żelazomanganu był niewystarczający, aby zapewnić kompletną redukcję tlenków.

Experimental research on the sintered steels with manganese own, in mixtures of powders obtained lead to the conclusion that in order to achieve homogeneity of the structural and mechanical characteristics comparable to those of the alloy steels commonly used in the powder metallurgy industry required high sintering temperatures and times . (1250 ° C and 120 min.).

Amorphous FeNiP nanoparticles with homogeneous composition are synthesized by reduction of aqueous Fe 2 + and Ni 2 + with sodium borohydride (NaBH 4 ) and hypophosphite at room temperature. These amorphous nanoparticles can be crystallized by heating up to 300 °C to form FeNi 3 and Ni 3 P crystals. Ni phase appeared at the sintering temperature of 500 °C, and a special net structure was formed at 700 °C due to the joining and diffusion among different nanoparticles. At a higher temperature of 800 °C, phase transformation happened and only pure Ni nanospheres and monoclinic ((Ni, Fe) 3 [PO 4 ] 2 ) nanorods can be observed, which should be governed by the long-range diffusion in the net structure. The amorphous FeNiP nanoparticles have excellent soft magnetic property with Ms of 13.2 emu/g and Hc of 0.7 Oe. However, the sintered mixing nanoparticles show varied magnetic properties due to the phase transformation and proportion change among different phases involved in. [ABSTRACT FROM AUTHOR]

Abstract: The application of chemometrics methods to continuous monitoring and diagnostics of sintering process faults for improving iron‐ore sinter quality is considered in the article. The sintering process is among complex multivariate processes. A number of agglomeration process faults have often similar symptoms, resulting in late fault detection by an operator and as a consequence, wrong process control decisions. To support the efficient operative decision making, it is proposed to use the process fault monitoring and diagnostics system. The proposed system uses a two‐level neural network (NN) diagnostic model. The high‐level neural network is used to localize the process faults whereas their reasons are determined by the low‐level neural networks. To reduce essentially the time of HL‐NN training and retraining, the task dimension is preliminarily reduced with the principal component analysis method so that the scores obtained from initial data are fed into high‐level neural network inputs. The use of principal component analysis allowed detection of sintering process faults with T2 and Q statistics. Only upon detecting the fault, a NN diagnostic model starts working to determine the fault reason. The system algorithm provides for special measures to prevent the NN from possible “loss” of the identified fault due to operator's inactivity. To increase the diagnosis depth for controlling fault symptoms that are evident on the sinter cake surface, optical digital cameras are installed and images from them are processed with proposed algorithms on the basis of fuzzy clusterization to take into account uncertainties in the initial information. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Real time resistance monitoring technology is used to study the silver sintering process. Signals of joint resistance show events such as resistance increase to >10 GΩ, abrupt resistance drop from >10 GΩ to <1 kΩ, and gradual resistance drop to <1 mΩ. Based on cross-sectioning of samples at various stages of sintering and differential scanning calorimetry (DSC), we propose a correlation between resistance signal and solvent evaporation, capping agent degradation, and silver sintering. We identified distinct clusters of sintered silver of samples removed from the oven when the resistance drops to ∼2.94 Ω. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate that persistent luminescent bodies can be obtained by carefully choosing the sintering temperatures and duration. A borosilicate and a phosphate glasses were sintered into bodies with persistent luminescent (PeL) SrAl 2 O 4 :Eu 2+ ,Dy 3+ microparticles which have a green emission up to tens of hours after ceasing irradiation. When sintered at high temperature for a short time or at lower temperature for a longer time, a decrease in the PeL from the bodies was observed and was related to the glasses crystallization. A decrease in the PeL from the bodies was also observed after immersion in simulated body fluid and was related to the mineralization of the sintered bodies. Therefore, we clearly show that by tracking the changes in the PeL overtime, these PeL bodies have a real potential application as biophotonic sensors to track dissolution and mineralization of the implant in the body. [ABSTRACT FROM AUTHOR]

In this article, the sintering process and particles migration mechanism of W-20wt%Cu composites sintered at 900°C for 660 s by thermal simulation instrument Gleeble-3500D were studied. The sintering process of the compacts was analyzed by dividing it into five stages and the sintering indexes at varied stages were calculated. Each sintering index corresponds to one particular kind of particles migration mechanism during a certain sintering stage. The results show that the sintering index is near infinitesimal in the first stage (0-10 s), and there will be relative slide and plastic deformation of particles. In the second stage (10-51 s), a sintering index of 1.24 is obtained, indicating plastic flow is the main mechanism of the particle migration. When it comes to the third stage (51-420 s), the index is found to be 2.34, implying the particle migration takes place by volume diffusion mechanism. The fourth stage (420-540 s) is with an index of 3.78 and surface diffusion is anticipated to be dominant in this stage. The last stage (540s-660 s) has an index of 2.92 and both volume diffusion and grain boundary diffusion prevail during this stage. [ABSTRACT FROM AUTHOR]

In this paper, the composite of low alloy steel reinforced with TiC particles was prepared by conventional powder metallurgy process. The effects of the combined carbon content of TiC powder, sintering temperature and heating rate on the composite were studied. The results showed that the selected TiC powder has a combined carbon content of 17.91 wt-% and the optimal sintering process is heating from 600 to 1440°C at a rate of 1°C min−1 and holding for 1 h at 1440°C. The composite after heat treatment has excellent mechanical properties with density of 6.45 g cm−3, hardness of 68–69 HRC and TRS of 1763 MPa, respectively, and will be used as wear-resistant parts, assembly fixtures, moulds, etc. [ABSTRACT FROM AUTHOR]

With the progressive deterioration in iron ore quality worldwide in recent years, steelmakers need to seek alternatives to mitigate the deficiency of this raw material. Investments in the use of high grade concentrate and the application of pre-agglomeration technologies are alternatives to make up for this deficit without affecting the utilization in the sintering process. As a possibility to avoid such investment, pellet screenings in comparison with the current natural sinter feed that can be found in the market, presents advantages such as low alumina and silica contents, but also low loss on ignition (LOI) and suitable particle size distribution. Sintering tests were performed at the SGA (Studiengesellschaft für Eisenerzaufbereitung) laboratory in Germany to evaluate the performance of this product when added to typical sintering mixtures used in Western Europe. The test results showed gains in the chemical, physical and metallurgical quality of the sinter produced. [ABSTRACT FROM AUTHOR]