Properties Of Slips Research Articles

Research of the dispersing and strengthening additives’ influence on the properties of slips and alumina ceramics samples from active alumina

The effect of dispersing and strengthening additives on the rheological properties of aqueous slips made from new brands of alumina produced by a German company was studied. The optimal quantities of dispersing additive for slips from all researched new brands of alumina were determined: for less dispersed alumina — 0.3 % and more dispersed alumina — 0.4 %, the introduction of which reduces the dynamic viscosity of slips to minimum values of — 30 mPa·s, 70 mPa·s and 110 mPa·s, respectively. It has been established that slips made from all researched new brands of alumina with the optimal dispersing additive quantity are characterized by high sedimentation stability and in combination with 0.2 % strengthening additive the sedimentation stability of slips increases.
 The main properties indexes of the samples from new brands of alumina before and after firing at a temperature of 1580 °C were determined. It was established that green samples from new brands of alumina are characterized by apparent density 2.23 g/cm3, 2.19 g/cm3, 2.18 g/cm3 and cold crushing strength 1.1 N/mm2, 1.0 N/mm2, 0.8 N/mm2, respectively, and samples after firing at 1580 °C by apparent density 3.75 g/cm3, 3.90 g/cm3, and 3.86 g/cm3, open porosity 3.3 %, 0.5 %, 0.4 % and bending strength 150 N/mm2, 180 N/mm2, 200 N/mm2, respectively.
 As a result of the performed research, it was established that new brands of more dispersed alumina are suitable for the production by the slip casting method in plaster molds of alumina ceramics with open porosity up to 0.5 % and bending strength ~ 180—200 N/mm2.
 According to the performed research results the technology of alumina ceramics by slip casting in plaster molds method was improved and the raw material base for its production was expanded.

Influence of Hall current & Lorentz force with nonlinear thermal radiation in an inclined slip flow of couple stress fluid over a Riga plate

Partially ionised fluids subject to an external magnetic field results in a completely different dynamical behaviour. Very few studies are conducted to explore the fascinating properties of Hall current and Ion slip in fluid flows. Flow over a Riga plate with MHD Ion and Hall currents, nonlinear thermal radiation is still rare. We aim to analyse the inclined stagnation point slip flow of Couple Stress fluid over a stretched horizontal Riga plate to close this gap. The flow problem is modelled using Navier stokes theory along with energy conservation and then principal partial differential equations are converted into ordinary differential equations. The governed system is solved mathematically by numerical technique RK Fehlberg method. The behaviour of fluid is described through graphs including fluid’s motion and energy. Local surface skin friction coefficients and local heat and mass flux at surface are the concerned physical magnitudes which are described through graphs and tables and are highly recommended in practical solicitations in numerous production plants and manufacturing workshops. Thermally radiative MHD flow with Ion Hall currents are broadly used in thermal controlling systems, spectro scopy, microchip technology, Magnetohydrodynamic energy conversion campaigns, exploration and expansion for high & low efficiency release, power-driven & power generation structures, MHD accelerations & thrusters, and drift regulator in hypersonic and automobiles.

Impact of the Xanthan Gum on Rheological and Mechanical Properties of Slip of Ceramic

The slips intended for the manufacture of ceramics must have rheological properties well-defined in order to bring together the qualities required for the casting step (good fluidity for feeding the molds easily settles while generating a regular settling of the dough and for the dehydration phase of the dough in the mold a setting time relatively short is required to have a sufficient refinement which allows demolding both easy and fast). Many additives have added in slip of ceramic in order to improve their rheological and mechanical properties. In this study, we investigated the impact of xanthan gum on rheological and mechanical properties of ceramic slip. The modified Cross model is used to fit the stationary flow curves of ceramic slip at different concentration of xanthan added. The addition of xanthan gum in a concentration range between 0 and 0.4 wt % in slip of ceramic induces the increase in the yield stress, zero shear rate viscosity and the infinite shear rate viscosity of the slip of ceramic. Generally speaking, the presence of xanthan gum modifies the rheological and mechanical properties of the slip. On the other hand, the study shows that an increase in flexural strength with the increase of the amount of xanthan gum in the ceramic slip. All the experimental results indicate an increasing tendency of the interactions between the particles of the raw materials with the highest concentration of xanthan gum.

The Potential of Al2O3\u2013ZrO2-Based Composites, Formed via CSC Method, in Linear Infrastructure Applications Based on Their Mechanical, Thermal and Environmental performance

Ceramic-ceramic composites have been prepared using the centrifugal slip casting method (CSC). The method has so far been mainly utilized in making ceramic-metal composites. Al2O3–ZrO2 composites have been obtained with different shares of ZrO2, i.e., 15, 50 and 75 vol pct, respectively. Prior to sintering the composite samples, the rheological properties of the casting slips were investigated and thermogravimetric tests were performed. Upon sintering, all three series of the ceramic composites showed a density close to 100 pct and no microcracks or delamination. Phase, microstructural and mechanical investigations were carried out to determine what effect the share of ceramics has on the composites produced. An increase in the share of ZrO2 in the Al2O3–ZrO2 composite leads to a reduction in the growth of Al2O3 grains and a decrease in the average hardness. Cross-sectional hardness testing of the composites showed no evident gradient in any of the samples. Life cycle analysis (LCA) results indicate that the further optimization of the composite formation process, including up-scaling, allows to obtain Al2O3–ZrO2-based pipes possessing more favorable environmental characteristics compared with materials conventionally used for linear infrastructure, which is important in light of the global transformation toward sustainable construction and the circular economy.Graphical abstract

Research of methods for introducing TiO2 nanoparticles into a micron matrix of BeO and TiO2 powders and their effect on the rheological properties of a casting slip

This article presents the research results of methods for introducing nanodispersed TiO2 powders into a micron matrix of beryllium and titanium oxides. It is shown that the presence of nanoparticles over 5.0 wt.% negatively affects the rheological properties of the casting slip and vice versa, the addition of nanoparticles in the range of 0.1–2.0 wt.% contributes to reducing the viscosity and increasing the casting ability of the slipping mass. Macrostructural analysis of the sintered billet indicates the complete absence of structural elements in the form of conglomerates of nanoparticles, or nano- and micro-TiO2 particles. The developed method of introducing nanoparticles makes it possible to obtain products with their uniform distribution over the entire volume of the workpiece by slip casting under pressure. Further, the authors of the scientific work planned to research the effect of nanoparticles on the thermophysical and impedance characteristics of the obtained ceramics. Research into the effect of nanopowders on the electrophysical properties of beryllium ceramics is not known in the scientific world. The most important properties that the BeO+TiO2 ceramics should possess is the ability to absorb ultrahigh frequency radiation, while it should heat up a little, i.e., conduct heat well. It is necessary to introduce the TiO2 phase into the composition of the BeO ceramics as much as possible to obtain a high coefficient.

Study of monotonic and cyclic mechanical behavior and microstructural evolution at a high temperature of ASTM A297 HP steel modified with niobium

The present work studies the effects of niobium on the mechanical properties and the elastoplastic/viscoelastic behavior at 927 °C of ASTM A297 grade, HP cast stainless steel in the as-cast material, to simulate the actual work condition. Tensile tests were carried out at different temperatures, differential scanning calorimetry (DSC), relaxation tests, the fatigue of continuous cycles under the triangular waveform, and fatigue with a trapezoidal waveform of the type “Dwell” with dwell times of 120 and 300 s as specified in the E2714-13 standard and hot torsion tests, to analyze the variations in the mechanical properties. The results of the mechanical tests and studies of the microstructural evolution, as well as of its later analyzes, provided data, not only in the form of data sheet's for the application of the values obtained in projects but concurrently after comparing property and microstructure, to deepen the phenomenology of mechanical stress behavior versus monotonic and cyclic deformation, high-temperature deformation mechanisms, dynamic recovery, of the type of microstructure resulting after the tests and also of the fracture mechanisms associated with the types of mechanical stresses imposed on the material, obtained by through the mechanical tests mentioned above. The high-temperature fatigue tests showed expected stress versus strain behavior, where cycles without dwell times showed lower hysteresis area values, from where the energy consumed in a strain cycle is calculated. The increase in the consumed energy values is due to the insertion of the dwell times, but it is important to note that for the tests that contain dwell times of 120 s and 300 s they did not show significant differences between the consumed energy, showing a saturation effect of tension that does not promote more significant inelastic strains. The cyclic mechanical fatigue stresses with dwell times and the low deformation rate led to intense precipitation of secondary carbides Cr23C6 chromium alloys added to the intrinsic properties of stainless steel dislocation slip were factors that resulted in the dynamic recovery phenomenon. Fractographic analyzes performed on monotonically fractured specimens and specimens after fatigue tests revealed that the material is prone to fracture in intergranular regions.

SLIPS-LAB-A bioinspired bioanalysis system for metabolic evaluation of urinary stone disease.

Urinary stone disease is among the most common medical conditions. Standard evaluation of urinary stone disease involves a metabolic workup of stone formers based on measurement of minerals and solutes excreted in 24-hour urine samples. Nevertheless, 24-hour urine testing is slow, expensive, and inconvenient for patients, which has hindered widespread adoption in clinical practice. Here, we demonstrate SLIPS-LAB (Slippery Liquid-Infused Porous Surface Laboratory), a droplet-based bioanalysis system, for rapid measurement of urinary stone-associated analytes. The ultra-repellent and antifouling properties of SLIPS, which is a biologically inspired surface technology, allow autonomous liquid handling and manipulation of physiological samples without complicated sample preparation procedures and supporting equipment. We pilot a study that examines key urinary analytes in clinical samples from patients with urinary stone. The simplicity and speed of SLIPS-LAB hold the potential to provide actionable diagnostic information for patients with urinary stone disease and rapid feedback for responses to dietary and pharmacologic treatments.

Slip Dökümle Üretilmiş Yunan Kırmızı Çamur Bünyelerin Sinterleme Özellikleri

Red mud is a solid waste residue of the digestion of bauxite ores with caustic soda for alumina production. There are several red mud sources in the world. The aim of this study was to identify the sintering conditions and technological properties of slip casted Greek red mud bodies. Chemical analysis of used greek red mud was determined by XRF. Slip casted samples were prepared with 40 vol. % solid content and sintered at 900, 950 and 1000 °C for 2h, seperately. Sintering and technological properties were determined by measuring density, firing shrinkage and water absorption. Structural characterization was carried out with scanning electron microscopy (SEM) and X-ray diffraction studies. The best density, water absorption, firing shrinkage values were obtained with Greek red mud body sintered at 1000°C. Artistic glaze was applied onto the Greek red mud bodies sintered at 1000°C. Glaze-body interaction were determined.

Research of the rheological and casting properties of alumina slips and samples from them containing a new dispersing addition and its combination with a hardening addition

The corundum ceramics technology has been developed and implemented at JSC “The URIR named after A. S. Berezhnoy”, which involves the production of high refractory corundum high density products using different methods of forming. A slip casting in gypsum form is one of the often used for forming a corundum ceramics production. The advantage of this method is the simplicity of the equipment, the relatively low cost of forms, as well as the possibility of manufacturing products of various shapes, sizes and weights.
 In depending of the wall thickness of the product using two methods of slip casting: bulk method with using a slip with a density of 2.5 g/cm3 of alumina MARTOXID brand with a dispersing addition (based on an aqueous solution of an ammonium salt of an acrylic copolymer) in an amount of 0.4 % for casting products of complex configuration, insulators, rods, plates, mortars, pestles, and for casting thick-walled products (4—5 mm and more) and a drain method with using a slip with a density of 2.1 g/cm3 of alumina MARTOXID brand with a dispersing addition in an amount of 0.3 % and a hardening addition in an amount of 0.2 % for casting hollow articles in the form of crucibles, covers, pipes, a ditch, boats, etc. for casting thin-walled products (1—3 mm).
 The researches of rheological properties of alumina slips from alumina MARTOXID brand which contain a new dispersing addition based on carboxylic acid and its combination with a hardening addition were carried out in this work.
 The optimum values of rheological and casting properties of the slips, ensuring the production of castings with a maximum density, are achieved with the introduction of 0.3 and 0.2 % dispersing addition into the slips with a density of 2.5 and 2.1 g/cm3 respectively were established.
 It was established that, at use of the dispersing addition based on carboxylic acid the apparent density of green body corundum ceramics lower than with the dispersing addition based on an aqueous solution of an ammonium salt of an acrylic copolymer, but it is sufficient to produce the same high-quality products after firing at 1580 оC (open porosity is not > 0.8 %) with a slightly higher shrinkage during firing, i. e. the use of this addition, if necessary, is possible.

Amelioration of mechanical and rheological characteristics of a ceramic Slip by adding of bentonite

This work is a contribution to the amelioration of the mechanical and rheological properties of a slip of ceramic used in the ceramic fabrication process. A study of characterization of slip of ceramic modified by bentonite has been accomplished chemically, physically, mechanically and rheologically. Chemical analysis showed that the slip modified by bentonite consist essentially of silica with a ratio (SiO_2/Al_2 O_3) average equal to 3.5 and the ratio of clays (Al2O3/SiO2) is relatively stable with increasing percentage of bentonite in the slip, with an average 0.28. The mechanical and rheological tests showing that increasing the percentage of bentonite in base slip caused an increase in the mechanical resistance, the yield stress and rapid decrease in density of the slip.

Improving of the mechanical and rheological properties of slip of ceramic

This work is a contribution to the amelioration of the mechanical and rheological properties of a slip of ceramic used in the ceramic fabrication process. A study of characterization of slip of ceramic modified by bentonite has been accomplished chemically, mechanically and rheologically. Chemical analysis showed that the slip modified by bentonite consist essentially of silica with a ratio of (SiO2/Al2O3) average equal to 3.5 and the ratio of clays (Al2O3/SiO2) is relatively stable with increasing percentage of bentonite in the slip, with an average of 0.28. The mechanical and rheological tests were showing that increasing the percentage of bentonite in the base slip caused an increase in the mechanical resistance, the yield stress and rapid increase in density of the slip.

Biomechanical and Morphometric Properties of the Long Flexor Tendons of the Toes: A Cadaver Study.

We sought to show the biomechanical and morphometric properties of flexor hallucis longus (FHL) and flexor digitorum longus (FDL) tendon grafts harvested by specific surgical approaches and to assess the contribution of FHL slips to the long flexor tendons of the toes. Thirteen fresh-frozen amputated feet (average age, 79 years) were dissected. The connections between the FHL and FDL tendons and the contribution of FHL slips to the long flexor tendons were classified. The biomechanical properties of the tendons and slips were measured using a tensile device. The connections between the FHL and FDL tendons were reviewed in two groups. Group 1 had FHL slips (11 cases) and group 2 had cross-slips (two cases). The FHL slips joined the second and third toe long flexor tendon structures. Tendon length decreased significantly from the second to the fifth toe (P < .001). Apart from the second toe tendon being thicker than that of the fourth toe (P = .02) and Young's modulus being relatively smaller in the third versus the fourth toe tendon (P = .01), biomechanical and morphometric properties of second to fourth tendons were similar. Mechanical properties of those tendons were significantly different from fifth toe tendons and FHL slips. Morphometric and biomechanical properties of FHL slips were similar to those of the fifth toe tendon. Herein, FHL slips were shown to have biomechanical properties that might contribute to flexor functions of the toes. During the harvesting of tendon grafts from the FHL by minimally invasive incision techniques from the distal plane of the master knot of Henry, cutting slips between FHL and FDL tendons could be considered a cause of postoperative function loss in toes.

Effect of Pigments on the Properties of Colored Slips for Porcelain Production

The effect of introducing into slip ceramic pigments of different types on the change in the properties of the slip is studied. The pigments have a thinning effect on the slip and increase the build-up rate of the intermediate-product wall.Water suspensions of ceramic pigments can be neutral, weakly acidic or weakly alkaline and change the rheological properties of the slips which they color: red and light-blue pigments decrease while brown and rose pigments increase the thickening factor and viscosity.

Researche influence of holding time on the rheological properties of alumina slips containing with dispersing and hardening additives and the properties of corundum ceramics samples which made from them

The researches influence of holding time on the rheological properties of the slips and the properties of corundum ceramics samples based on alumina of the MARTOXID MR70 brand with dispersing and hardening additives (for casting thin-walled products) and only with the dispersing additive (for casting of thick-walled products) which made of them were carried out. The holding time has a significant effect on the rheological properties of the slips were established. The destruction of aggregates in initial alumina on particles were begining with increasing the holding time the slips to 24 hours as a result the dynamic viscosity of these slips decreases and reaches a minimum value. In the slips with combined additive (dispersing and hardening) with increasing the holding time more than 24 hours beginning the formation of a coagulation-condensation structure. In the slip with only a dispersing additive and in the slips without additive beginning the formation of a coagulation structure the dynamic viscosity of the slips increases and this process does not end at 672 hours. However, with a little mechanical mixing in all three slips their structure are fragile and easily almost completely destroyed and such slips are suitable for making quality products from them. The samples which made from the slips after a holding time of 24 hours and 720 hours have practically the same properties, so the increasing the holding time for more than 24 hours does not affect the properties of the samples. For making quality products the fresh slips are also suitable and it is necessary to choose the holding time of slips according to the size and configuration of products, their service conditions and production volumes. According to the electronicmicroscopic studies the formation a gel-like substance that envelops alumina particles and thereby prevents its settling in the slip which contains the hardening additive.

Evidence for Truncated Exponential Probability Distribution of Earthquake Slip

Earthquake ruptures comprise spatially varying slip on the fault surface, where slip represents the displacement discontinuity between the two sides of the rupture plane. In this study, we analyze the probability distribution of coseismic slip, which provides important information to better understand earthquake source physics. Although the probability distribution of slip is crucial for generating realistic rupture scenarios for simulation‐based seismic and tsunami‐hazard analysis, the statistical properties of earthquake slip have received limited attention so far. Here, we use the online database of earthquake source models (SRCMOD) to show that the probability distribution of slip follows the truncated exponential law. This law agrees with rupture‐specific physical constraints limiting the maximum possible slip on the fault, similar to physical constraints on maximum earthquake magnitudes. We show the parameters of the best‐fitting truncated exponential distribution scale with average coseismic slip. This scaling property reflects the control of the underlying stress distribution and fault strength on the rupture dimensions, which determines the average slip. Thus, the scale‐dependent behavior of slip heterogeneity is captured by the probability distribution of slip. We conclude that the truncated exponential law accurately quantifies coseismic slip distribution and therefore allows for more realistic modeling of rupture scenarios. Online Material: Figures showing scaling of slip area with seismic moment and Q – Q plots and tables listing earthquakes, rupture models, and fits of various distributions to the empirical probability distribution.

Overturned folds in ice sheets: Insights from a kinematic model of traveling sticky patches and comparisons with observations

AbstractOverturned folds are observed in regions of the Greenland ice sheet where driving stress is highly variable. Three mechanisms have been proposed to explain these folds: freezing subglacial water, traveling basal slippery patches, and englacial rheological contrasts. Here we explore how traveling basal sticky patches can produce overturned folds. Transitions from low to high stress cause a tradeoff in ice flow between basal slip and internal deformation that deflects ice stratigraphy vertically. If these transitions move, the slip‐deformation tradeoff can produce large folds. Those folds record the integrated effects of time‐varying basal slip. To understand how dynamic changes in basal slip influence ice sheet stratigraphy, we develop a kinematic model of ice flow in a moving reference frame that follows a single traveling sticky patch. The ice flow field forms a vortex when viewed in the moving reference frame, and this vortex traps ice above the traveling patch and produces overturned folds. Sticky patches that travel downstream faster produce larger overturned folds. We use the model as an interpretive tool to infer properties of basal slip from three example folds. Our model suggests that the sticky patches underneath these folds propagated downstream at rates between one half and the full ice velocity. The regional flow regime for the smaller two folds requires substantial internal deformation whereas the regime for the largest fold requires substantially more basal slip. The distribution and character of stratigraphic folds reflect the evolution and propagation of individual sticky patches and their effects on ice sheet flow.

The Experimental of Low Temperature Color Slip for Decorative on Earthenware Body

The purpose of the study was to investigate the effects of dolomite body, frit and potassium feldspar on the properties of color slip for decorative method of color slip on earthen ware production. The characterization of raw material was analyzed by X-ray fluorescence (XRF). The experiment started with triaxial blend of dolomite body, frit and potassium feldspar in the defined ratio and then to painting of color slips on earthenware production. After that, firing specimens at 950 °C in oxidation atmosphere. Finally, the specimens were tested microstructure and physical properties. The results showed that the ratio of 50% dolomite body, 40% frit and 10% potassium feldspar were optimum properties for decorative on earthenware body. In color slip consisting of blue color added Cobalt oxide 1% ,Green colors added chromic oxide 10% , Gray color added manganese oxide 10% ,yellow color added stain 2225 10% and hazel color added ferric oxide 2 wt %.

Rheological Properties of Porcelain Slip with Biosurfactants

The effect of nutrient liquids with the bacteria Acinetobactre johnsii str. J221 and Pseudomonas aeruginosa str. G.d. on the rheological properties of porcelain slip is studied. The surface activity of the nutrient liquid promotes a reduction of the fluidity and thixotropic hardening of porcelain slip. The mass increase of the casting upon pouring is due to the hydrophobization of the surface of the slip particles. The thickening of the porcelain slip is interrelated with the change in the redox state of the medium from weakly to strongly basic, favorable for the development of an aborigennic community of anaerobic microorganisms.

Corundum-Based Substrates for Membrane Processes

Aspects of a technology for producing tubular corundum-based substrates for membranes are examined. The ratios of the components and the rheological properties of slip are determined. Experiments on the deposition of a selective layer on a substrate are performed. The composition and technology developed for fabricating blanks make it possible to create substrates with open channel porosity of the order of 42%, pore size no more than 1 μm, and ultimate strength in bending 20 MPa.

Technological Properties of Ceramic Slip with Oxyethylidenediphosphonic Acid in a Complex Deflocculent

The composition of a complex deflocculent for ceramic slip based on oxyethylidenediphosphonic acid (OEDPA) and components of a conventional thinner containing liquid glass and soda is found by trial and error. A comparative study is performed of the effect of the proposed deflocculent and the deflocculent Reotan SL (Lamberti Co.) on the rheological properties of the ceramic slip modified by them and the physical-mechanical properties of the castings. The deflocculent containing OEDPA makes it possible to minimize the slip thixotropy for which the casting rate of the samples, characterized by higher shrinkage and characteristics, remains high.