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An attempt was made to precipitate highly dispersed carbonate‐silicate fillers from solutions of metasilicate sodium and calcium hydroxide using gaseous carbon dioxide. Optimum conditions were defined for precipitating these powders. Carbonate‐silicate fillers were subjected to surface modification employing two techniques: the wet one, applied in the course of precipitation, and the dry one. For the modification, silane coupling agents were used. The carbonate‐silicate fillers were subjected to physicochemical analysis. Moreover, particle size distribution was determined using the DLS technique and their surface morphology was examined using SEM. The modified carbonate‐silicate filler was applied as a substitute of titanium white and a filler in acrylic paints.i

Fillers with different chemical properties were used to study their effects on poly(vinyl acetate) (PVAc) emulsion wood adhesives. The elastoplastic behaviour of the filler treated PVAc emulsions was studied using differential scanning calorimetry and dynamic mechanical thermal analysis. The results show that the glass transition temperature (T_g) of the polymer is not changed significantly by the addition of the fillers, while the tensile modulus is changed together with the hardness and stiffness. The viscosity of the emulsions and their performance on wood surfaces are greatly affected by fillers. Fillers with high oil‐absorption capacity increase viscosity to a greater extent. The acidity of the fillers influences the setting time for bonding of the emulsions to wood, and the water resistance, since some chemical reactions can take place during curing.

Reports on tests in which barium metaborate pigment and its modified form are prepared, identified by chemical and X‐ray diffraction methods, and specified according to standard methods. Evaluates the modified barium metaborate as a new filler for paper making by carrying out two series of experiments. Details the results which showed that the efficiency of the filler retention when using modified barium metaborate was higher than that of the other two conventional fillers. Reveals that at relatively low filler addition (2–5 percentage weight), higher improvement in the strength properties can be obtained when using the modified pigment instead of titanium dioxide and kaolin, but observes the reverse (i.e. a detrimental effect) at relatively high filler addition (8–10 percentage weight). Discovers that the optical properties of the modified pigment‐loaded sheets lie between those of titanium dioxide and kaolin. Shows that blending barium metaborate with kaolin or titanium dioxide has a significant effect on strength properties rather than optical properties. Concludes that modified barium metaborate pigment can be successfully used in paper filling applications and that modified barium metaborate pigment‐kaolin blend (80/20 per cent) can be used instead of titanium dioxide as a paper filler.

This study aims to propose a semiempirical and semitheoretical cyclic compaction constitutive model of coarse-grained soil filler for the high-speed railway (HSR) subgrade under cyclic load.

According to the basic framework of critical state soil mechanics and in view of the characteristics of the coarse-grained soil filler for the HSR subgrade to bear the train vibration load repeatedly for a long time, the hyperbolic empirical relationship between particle breakage and plastic work was derived. Considering the influence of cyclic vibration time and stress ratio, the particle breakage correction function of coarse-grained soil filler for the HSR subgrade under cyclic load was proposed. According to the classical theory of plastic mechanics, the shearing dilatation equation of the coarse-grained soil filler for the HSR subgrade considering particle breakage was modified and obtained. A semiempirical and semitheoretical cyclic compaction constitutive model of coarse-grained soil filler for the HSR subgrade under cyclic load was further established. The backward Euler method was used to discretize the constitutive equation, build a numerical algorithm of “elastic prediction and plastic modification” and make a secondary development of the program to solve the cyclic compaction model.

Through the comparison with the result of laboratory triaxial test under the cyclic loading of coarse-grained soil filler for the HSR subgrade, the accuracy and applicability of the cyclic compaction model were verified. Results show that the model can accurately predict the cumulative deformation characteristics of coarse-grained soil filler for the HSR subgrade under the train vibration loading repeatedly for a long time. It considers the effects of particle breakage and stress ratio, which can be used to calculate and analyze the stress and deformation evolution law of the subgrade structure for HSR.

The research can provide a simple and practical method for calculating deformation of railway under cyclic loading.

The purpose of this study is to develop jute-glass hybrid fibre reinforced polyester-based bio-composites using an indigenously developed pultrusion set-up and to present a detailed discussion on their mechanical characterization.

The work was carried out to observe the hybridization effect of natural and synthetic fibres in combination with hybrid fillers loading mainly on strength and other properties. The used hybrid fillers were a combination of 9 Wt.% of carbon black%, 6 Wt.% of eggshell ash powder and 6 Wt.% of coconut coir ash powder. A lab-based developed pultrusion set-up was used to develop these hybrid GJFRP composites of 1,500 mm length. The developed composites were tested for tensile strength, compressive strength and impact strength.

The maximum tensile, compressive and impact strength obtained are 88.37 MPa, 56.13 MPa and 731.91 J/m from 9 Wt.%, 9 Wt.% and 0 Wt.% of hybrid fillers loading, respectively. Breaking energy was found maximum as 7.31 J in hybrid glass-jute hybrid fibre reinforced plastic composites with no filler loading and it was observed that filler loading was decreasing the impact strength of developed hybrid composites. Shrinkage and its variations in the diameter of the finally developed cylindrical shape composites were observed after cooling and solidification. Scanning electron microscopy was used to observe the internal cracks, bonding of fibres and resin, voids, etc.

Development of hybrid filler based novel eco-friendly bio-composites and its experimental investigation on the impact strength, tensile strength and compressive strength has not been attempted yet.

The purpose of this paper is to prepare stabile emulsions with 0–15% of colloidal silica and high monomer/water ratio and to investigate the influence of silica addition and surface modification on the polyacrylate properties.

Improving the properties of the composite can be achieved by optimizing the compatibility between the phases of the composite system with improving the interactions at the matrix/filler interface. Therefore, the silica surface was modified with nonionic emulsifier octylphenol ethoxylate, cationic initiator 2,2'-azobis-(amidinopropane dihydrochloride) and 3-methacryloxypropyltrimethoxysilane and polyacrylate/silica nanocomposites were prepared via in situ emulsion polymerization. Particle size distribution, rheological properties of the emulsions and morphology, thermal properties and mechanical properties of the film prepared from the emulsions were investigated.

Polyacrylate/silica systems with unmodified silica, silica modified with nonionic emulsifier and cationic initiator have micrometer, while pure PA matrix and systems with silica modified with silane have nanometer particle sizes. Addition and surface modification of the filler increased emulsion viscosity. Agglomeration of silica particles in composites was reduced with silica surface modification. Silica filler improves thermal stability and tensile strength of polyacrylate.

This paper provides broad spectrum of information depending on filler surface modification and latex preparation via in situ emulsion polymerization and properties with high amount of filler and monomer/water ratio with the aim that prepared latex is suitable for film formation and final application.

Rapid tooling (RT) integrated with additive manufacturing technologies have been implemented in various sectors of the RT industry in recent years with various kinds of prototype applications, especially in the development of new products. The purpose of this study is to analyze the current application trends of RT techniques in producing hybrid mold inserts.

The direct and indirect RT techniques discussed in this paper are aimed at developing a hybrid mold insert using metal epoxy composite (MEC) in increasing the speed of tooling development and performance. An extensive review of the suitable development approach of hybrid mold inserts, material preparation and filler effect on physical and mechanical properties has been conducted.

Latest research studies indicate that it is possible to develop a hybrid material through the combination of different shapes/sizes of filler particles and it is expected to improve the compressive strength, thermal conductivity and consequently increasing the hybrid mold performance (cooling time and a number of molding cycles).

The number of research studies on RT for hybrid mold inserts is still lacking as compared to research studies on conventional manufacturing technology. One of the significant limitations is on the ways to improve physical and mechanical properties due to the limited type, size and shape of materials that are currently available.

This review presents the related information and highlights the current gaps related to this field of study. In addition, it appraises the new formulation of MEC materials for the hybrid mold inserts in injection molding application and RT for non-metal products.

Friction stir welding (FSW) butt-joining involving the use of a dissimilar filler metal insert between the retreating and advancing portions of the workpiece is investigated computationally using a combined Eulerian-Lagrangian (CEL) finite element analysis (FEA). The emphasis of the computational analysis was placed on the understanding of the inter-material mixing and weld-flaw formation during a dissimilar-material FSW process. The paper aims to discuss these issues.

The FEA employed is of a two-way thermo-mechanical character (i.e. frictional-sliding/plastic-work dissipation was taken to act as a heat source in the energy conservation equation), while temperature is allowed to affect mechanical aspects of the model through temperature-dependent material properties. Within the analysis, the workpiece and the filler-metal insert are treated as different materials within the Eulerian subdomain, while the tool was treated as a conventional Lagrangian subdomain. The use of the CEL formulation within the workpiece insert helped avoid numerical difficulties associated with excessive Lagrangian element distortion.

The results obtained revealed that, in order to obtain flaw-free FSW joints with properly mixed filler and base materials, process parameters including the location of the tool relative to the centerline of the weld must be selected judiciously.

To the authors’ knowledge, the present work is the first reported attempt to simulate FSW of dissimilar materials.

The purpose of this paper is to study the effect of incorporating some inorganic fillers, namely aluminium oxide and aluminium hydroxide on the rheological, mechanical and thermal behaviour of acrylonitrile‐butadiene rubber (NBR) vulcanizates.

For improving physico‐mechanical properties of NBR vulcanizates, various compositions were made by incorporating different concentrations of employed fillers with NBR. These properties included the torque, cure time, tensile strength, elongation at break, swelling, diffusivity, as well as thermal behaviour of the loaded and unloaded NBR with fillers were characterised.

The incorporation of the two investigated fillers improves the thermal behaviour of the vulcanizates, especially aluminium hydroxide. All samples showed more or less a first order decomposition kinetics, for which the activation energy ranged from 177 to 187 kg/mol.

NBR is extensively used industrially for its single, most important property, which is an exceptional resistance to attack by oils and solvents. However, incorporation of fillers in (NBR) leads to the development of improved, competitive properties of the vulcanizate. A further study must be carried out on the flame retarding effect of the fillers, beside the effect of surface treatment of the fillers on the dispersibility and physico‐mechanical properties of the vulcanizates.

The use of two investigated fillers provided a simple and practical solution to improving the resistance to swelling in motor and break oil as well as the thermal behaviour of the NBR.

The use of these fillers was novel and could be used in many rubber industries especially in gasket and oil seals.

Multiple fillers are adopted to study the filler influences on electrical and mechanical properties of the conductive adhesives. The performances of the developed nano-enhanced interconnect materials in printing process are also evaluated. The paper aims to discuss these issues.

Micron-sized silver flakes are used as the basic fillers, and submicro- and nano-sized silver spheres and carbon nanotubes (CNTs) are adopted to obtain conductive adhesives with multiple fillers. Differential scanning calorimetry measurement is carried out to characterize the curing behavior of the samples with different fillers, four-probe method is used to obtain the bulk resistivity, shear test is conducted for adhesive strength, and environmental loading test is also involved. Furthermore, printing trials with different patterns have been carried out.

The electrical resistivity of the adhesives with submicro-sized silver spheres does not monotonically change with the increasing sphere proportion, and there exists an optimized value for the ratio of silver flakes to spheres. Samples with relatively small amount of CNT additives show improved electrical properties, while their mechanical strengths tend to decrease. For the printing application, the adhesives with 18.3 volume% filler content behave much better than those with lower filler content of 6 percent. The presence of the nano-particles makes a slight improvement in the printing results.

More detailed printing performance and reliability test of the samples need to be carried out in the future.

The conductive adhesives as interconnect materials exhibit some improved properties with optimized bimodal or trimodal fillers. The additive of the nano-fillers affects slightly on the printing quality of the bimodal conductive adhesives.