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This study aims on a broad review of Concrete's Rheological Properties. The Concrete is a commonly used engineering material because of its exquisite mechanical interpretation, but the addition of constituent amounts has significant effects on the concrete’s fresh properties. The workability of the concrete mixture is a short-term property, but it is anticipated to affect the concrete’s long-term property.

In this review, the concrete and workability definition; concrete’s rheology models like Bingham model, thixotropy model, H-B model and modified Bingham model; obtained rheological parameters of concrete; the effect of constituent’s rheological properties, which includes cement and aggregates; and the concrete’s rheological properties such as consistency, mobility, compatibility, workability and stability were studied in detail.

Also, this review study has detailed the constituents and concrete’s rheological properties effects. Moreover, it exhibits the relationship between yield stress and plastic viscosity in concrete’s rheological behavior. Hence, several methods have been reviewed, and performance has been noted. In that, the abrasion resistance concrete has attained the maximum compressive strength of 73.6 Mpa; the thixotropy approach has gained the lowest plastic viscosity at 22 Pa.s; and the model coaxial cylinder has recorded the lowest stress rate at 8 Pa.

This paper especially describes the possible strategies to constrain improper prediction of concrete’s rheological properties that make the workability and rheological behavior prediction simpler and more accurate. From this, future guidelines can afford for prediction of concrete rheological behavior by implementing novel enhancing numerical techniques and exploring the finest process to evaluate the workability.

The purpose of this paper is to study the rheological behaviours of lead‐free solder pastes used for flip‐chip assembly applications and to correlate rheological behaviours with the printing performance.

A range of rheological characterization techniques including viscosity, yield stress, oscillatory and creep‐recovery tests were carried out to investigate the rheological properties and behaviours of four different solder paste formulations based on no‐clean flux composition, with different alloy composition, metal content and particle size. A series of printing tests were also conducted to correlate printing performance.

The results show that in the viscosity test, all solder pastes exhibited a shear thinning behaviour in nature with different highest maximum viscosity. The yield stress test has been used to study the effect of temperature on the flow behaviour of solder pastes. A decrease in yield stress value with temperature was observed. The results from the oscillatory test were used to study the solid‐ and liquid‐like behaviours of solder pastes. Creep‐recovery testing showed that the solder paste with smaller particle size exhibited less recovery.

More extensive research is needed to simulate the paste‐roll, aperture‐filling and aperture‐emptying stages of the stencil printing process using rheological test methods.

Implementation of these rheological characterization procedures in product development, process optimization and quality control can contribute significantly to reducing defects in the assembly of flip‐chip devices and subsequently increasing the production yield.

The paper shows how the viscosity, yield stress, oscillatory and creep‐recovery test methods can be successfully used to characterize the flow behaviour of solder pastes and also to predict their performance during the stencil printing process.

The aim of this paper is to characterize the rheological properties of the flux media exposed to different levels of solicitation and to determine its influence on the rheology of the solder paste. The data obtained experimentally are fundamental for the development of numerical models that allow the simulation of the printing process of printed circuit boards (PCB).

Rheological tests were performed using the Malvern rheometer Bohlin CVO. These experiments consist of the analysis of the viscosity, yield stress, thixotropy, elastic and viscous properties through oscillatory tests and the capacity to recover using a creep-recovery experiment. The results obtained from this rheological analysis are compared with the rheological properties of the solder paste F620.

The results have shown that the flux is viscoelastic in nature and shear thinning. The viscosity does not decrease with increasing solicitations, except in the case where the flow is withdrawn directly from the bottle. Even if the solder paste shows a thixotropic behavior, this is not the case of the flux, meaning that this property is given by the metal particles. Furthermore, the oscillatory tests proved that the flux presents a dominant solid-like behavior, higher than the solder paste, meaning that the cohesive/tacky behavior of the solder paste is given by the flux.

To complement this work, printing tests are required.

This work demonstrates the importance of the rheological characterization of the flux in order to understand its influence in the solder paste performance during the stencil printing process.

The purpose of this paper is to investigate the rheological behaviour of three different lead‐free solder pastes used for surface mount applications in the electronic industry.

This study concerns the rheological measurements of solder paste samples and is made up of three parts. The first part deals with the measurement of rhelogical properties with three different measuring geometries, the second part looks into the effect of frequencies on oscillatory stress sweep measurements and the final part reports on the characterisation and comparison of three different types of Pb‐free solder pastes.

Among the three geometries, the serrated parallel plate was found effective in minimising the wall‐slip effect. From the oscillatory stress‐sweep data with different frequencies; it was observed that the linear visco‐elastic region is independent of frequency for all the solder paste samples. To understand the shear thinning behaviour of solder paste, the well known Cross and Carreau models were fitted to the viscosity data. Moreover, creep‐recovery and dynamic frequency‐sweep tests were also carried out without destroying the sample's structure and have yielded useful information on the pastes behaviour.

More extensive research is needed to fully characterise the wall‐slip behaviour during the rheological measurements of solder pastes.

The rheological test results presented in this paper will be of important value for research and development, quality control and facilitation of the manufacturing of solder pastes and flux mediums.

This paper shows how wall‐slip effects can be effectively avoided during rheological measurements of solder pastes. The paper also outlines how different rheological test methods can be used to characterise solder paste behaviours.

This study aims to investigate rheological and extrusion behavior of thermosetting epoxy resins, which to find the universal property and printing parameters for extrusion-based rapid prototyping applications.

The thickener proportion greatly influences its viscosity and rheological behavior and therefore plays an important role in the shape of the cross-section of the extrudate.

A pseudoplastic (shear-thinning) is a basic requirement for obtaining extruded lines with plump cross-sections. In addition to the effects of the rheological behavior of the composite, shape maintenance and its wettability on the substrate, the cross-sectional geometry of the extrudate is also strongly affected by printing process parameters including the extrusion nozzle height, nozzle moving speed, extrusion rate and critical nozzle height. Proper combinations of these process parameters are necessary to obtain single-line extrudates with plump cross-sections and 3-D objects with dimensional accuracy, uniform wall thickness, good wall uprightness and no wall slumping. Formulas and procedures for determining these extrusion parameters are proposed and demonstrated in experiments.

The results obtained have been explained in terms of the interactions among the rheological properties of the composite, the shear rate imposed on the composite during extrusion, the wettability of the composite on the substrate and the shape maintenance of the composite during extrusion.

Fabrication settings such as printing speed and nozzle temperature in fused deposition modeling undeniably influence the quality and strength of fabricated parts. As available market filaments do not contain any exact information report for printing settings, manufacturers are incapable of achieving desirable predefined print accuracy and mechanical properties for the final parts. The purpose of this study is to determine the importance of selecting suitable print parameters by understanding the intrinsic behavior of the material to achieve high-performance parts.

Two common commercial polylactic acid filaments were selected as the investigated samples. To study the specimens’ printing quality, an appropriate scaffold geometry as a delicate printing sample was printed according to a variety of speeds and nozzle temperatures, selected in the filament manufacturer’s proposed temperature range. Dimensional accuracy and qualitative surface roughness of the specimens made by one of the filaments were evaluated and the best processing parameters were selected. The scaffolds were fabricated again by both filaments according to the selected proper processing parameters. Material characterization tests were accomplished to study the reason for different filament behaviors in the printing process. Moreover, the correlations between the polymer structure, thermo-rheological behavior and printing parameters were denoted.

Compression tests revealed that precise printing of the characterized filament results in more accurate structure and subsequent improvement of the final printed sample elastic modulus.

The importance of material characterization to achieve desired properties for any purpose was emphasized. Obtained results from the rheological characterizations would help other users to benefit from the highest performance of their specific filament.

The purpose of this paper was to study the effect of botanical origin on the characteristics of single-flower honeys (assa-peixe, coffee, eucalyptus, laranjeira and vassourinha), polyfloral (silvestre), extrafloral (sugarcane) and honeydew (bracatinga) during storage.

The honeys were stored at 14 °C, and the analysis of water activity, color, absorbance, rheological behavior and microscopic analysis were performed during 6 months (T0, T30, T60, T90, T120, T150 and T180 days); quantification of sugars (fructose (F) and glucose (G)), moisture (M), F/G and G/M ratio only at T0.

All honeys showed changes during storage, and sugarcane honey stood out for presenting greater crystallization, influenced by the high content of glucose and fructose. Coffee honey showed the least crystallization. The crystallization of honeys influenced the increase in water activity, Newtonian viscosity, color and absorbance. The composition of the honeys directly influenced the crystallization process during storage.

Crystallization is a natural process that occurs spontaneously in honey. Thus, the knowledge of the crystallization rate of honeys from different origins (botanical and geographical) during storage, is of great importance and interest for the industry, beekeepers and consumers, since each type of honey crystallizes in different ways and periods.

Hyperbranched poly(ester-amide)s (HPEAs) have been synthesized from diethanolamine and maleic anhydride with ethylene glycol as a core monomer by using a two-step method, which are marked as Hupea polymers, and dehydration was carried out in xylene under reflux.

In comparison with Hupea polymers was synthesized by one-pot method, Hupea polymers synthesized by two-step method has different structure and rheological properties. The intermediate monomer and the resulting polymer are characterized by FTIR and NMR spectroscopies.

All of Mw, Mn and Mw/Mn of the hyperbranch polymers decrease with the core/monomer molar ratio increasing. The intrinsic viscosity ([η]) of the polymers decreases with Mw increasing in the investigated range of Mw and scales as [η]∼Mw-0.82, which implies that the molecular weight grew faster with core/monomer molar ratio decreasing than the volume in the investigated range of core/monomer molar ratio.

The hydrodynamic radius was calculated by using Einstein’s equation and scales as Rh ∼ Mw0.061, and the lower exponent reveals the slow growth in the volume of Hupea molecule. In addition, the viscosity of Hupea polymer in concentrated aqueous solution is independent of shear rate and slightly dependent on molecular weight.

Hyperbranched poly(ester-amide)s (HPEAs) were synthesized by using a two-step method, which had different structure and rheological properties.

Hupea polymers show different features from Hupea polymers in structure and rheological properties, which revealed that the synthesis process of HPEA has effect on its performance.

This paper aims to investigate the vital characteristic of an innovative ceramic injection molding (CIM) process for orthopedic application with controlled porosity and improved tribological and mechanical properties which were affected by complex tribological interactions, whether lubricated like hip implants and other artificial prostheses. The main objective is to maximize the usage of palm stearin as a single based binder as the function of flow properties during injection molding process.

The binder used in this present study consists of 100 per cent palm stearin manufactured by Kempas Oil Sdn Bhd and supplied by Vistec Technology Sdn Bhd. The feedstock was prepared by using a Z-blade mixer (Thermo Haake Rheomix OS) and Brabender mixer model R2400. The feedstock prepared was injection molded using a manually operated vertical benchtop machine with an average pressure of about 5-7 bars. The firing step included the temporary holds at intermediate temperatures to burn out organic binders. At this stage, the green molded specimen was de-bound using a single-step wick-debinding method.

The maximum content of ceramic material is applied to investigate the efficiencies of net formulation that can be achieved by ceramic materials. The longer the viscosity will change with shear rate, the higher the value of n obtained instead. From the slope of the curves obtained in Figure 3, the value of n for the feedstock was determined to be less than 1, which indicates a pseudoplastic behavior and suitability for the molding process. Moreover, high shear sensitivity is important in producing complex and intrinsic specimens which are leading products in the CIM industry.

The feedstock containing HAp powder and palm stearin binder was successfully prepared at very low temperature of 70°C, which promoting a required pseudo-plastic behavior during rheological test. The single binder palm stearin should be optimized in other research works carried out, as palm stearin is most preferred compared to other polymeric materials that provided high energy consumption when subjected to the sintering process. Besides the binder is widely available in Malaysia, low cost and harmless effect during debinding process.

The aim of this study is to develop a soy‐based cream cheese (SCC) with textural characteristics comparable to that of commercial dairy cream cheese (DCC) via the addition of microbial transglutaminase (MTG), soy protein isolate (SPI) and maltodextrin (MD).

Response surface methodology (RSM) was employed in this study to determine the effects of MTG, MD and SPI on firmness of SCC.

The second‐order model generated via RSM was significant with only a 9.76 per cent variation not explained by the model. The coefficient of regression revealed that MTG, MD and SPI showed significant linear effects (P<0.0001) on the firmness of SCC, while MTG and SPI showed significant quadratic effects. The model successfully predicted and developed a SCC model with similar firmness as that of DCC; via the combination of 2.57 per cent (w/w) of MTG, 19.69 per cent (w/w) of SPI and 19.69 per cent (w/w) of MD. Physicochemical analyses revealed that SCC possessed lower fat content, reduced saturated fatty acid and zero trans fat. Further rheological measurements revealed that SCC was more solid‐like at room temperature, but less elastic at refrigerated temperature compared to DCC. SEM and SDS‐PAGE analyses affirmed that the textural changes of SCC were attributed to MTG‐induced cross‐linking.

The research demonstrated that a non‐dairy cream cheese could be developed using soy. In addition, the SCC also contained better nutritional properties compared to its dairy counterpart.