Effects of Trammonium Citrate on Slurry of PMN-PZT in Gelcasting Process

2012 ◽  
Vol 476-478 ◽  
pp. 1050-1053 ◽  
Author(s):  
Jing Hong Du ◽  
Guo You Gan ◽  
Ji Kang Yan ◽  
Jian Hong Yi ◽  
Jia Min Zhang

Preparation of aqueous ceramics slurry with high solid volume and low viscosity is premise and key step of gelcasting, and dispersant play important role in slurry preparation. In this paper, triammonium citrate (TAC) was used as dispersant of PMN-PZT piezoelectric ceramics slurry, the effects of TAC on slurry stability and rheological properties and dispersion mechanism of TAC were investigated by sedimentation test, viscosity, scanning electron microscopy (SEM) and FTIR analysis. The SEM results indicated that TAC could reduce the agglomeration of powder particles and make ceramic particles well-dispersed. FTIR indicated that strong chemical absorption occurred between TAC and PMN-PZT powder, and slurry stability and rheological properties of PMN-PZT slurry were improved through electrostatic interaction of TAC. The effects of TAC on sedimentation volume and viscosity have similar tendency. When TAC content was 7.5vol% and pH of slurry was about10, PMN-PZT slurry suitable for gel-casting could be acquired.

Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 681
Author(s):  
Monika Sterczyńska ◽  
Marek Zdaniewicz ◽  
Katarzyna Wolny-Koładka

During the production of beer, and especially beer wort, the main wastes are spent grain and hot trub, i.e., the so-called “hot break.” Combined with yeast after fermentation, they represent the most valuable wastes. Hot trub is also one of the most valuable by-products. Studies on the chemical composition of these sediments and their rheological properties as waste products will contribute to their effective disposal and even further use as valuable pharmaceutical and cosmetic raw materials. So far, hot trub has been studied for morphology and particle distribution depending on the raw material composition and beer wort extract. However, there are no preliminary studies on the rheological properties of hot trub and hops. In particular, no attention has yet been paid to the dependence of these properties on the hop variety or different protein sources used. The aim of this study was to examine the effect of different hopping methods on hot trub viscosity and beer wort physicochemical parameters. Additionally, the hop solutions were measured at different temperatures. A microbiological analysis of hop sediments was also performed to determine the post-process survival of selected microorganisms in these wastes. For manufacturers of pumps used in the brewing industry, the most convenient material is that of the lowest viscosity. Low viscosity hot trub can be removed at lower velocities, which reduces costs and simplifies washing and transport. The sediments also had similar equilibrium viscosity values at high shear rates.


2020 ◽  
pp. 095400832098343
Author(s):  
Xiaomu Wen ◽  
Ximing Zhang ◽  
Keke Chen ◽  
Yunjun Luo

Both better mechanical and rheological properties are pursued for composite solid propellant. In this work, varying proportions of a modified hyperbranched polyester (MHBPE) were added to HTPE/AP/Al propellant. The static tensile property as one kind of mechanical properties of MHBPE/HTPE/AP/Al propellant were found to be superior to those of blank HTPE/AP/Al propellant as a result of the entanglement and interpenetration of molecular chains caused by the introduction of the hyperbranched structure. Evaluations on the related improved creep resistance and stress relaxation performance further demonstrated the advantages of introduction of MHBPE to HTPE/AP/Al propellant. Rheological properties of HTPE/AP/Al propellant with and without MHBPE during the casting process were investigated and compared and the results confirmed the improvement benefiting from low viscosity and loose void structure. Thus, modified hyperbranched polyester provided a novel route to potentially meet the requirements for propellant manufacturing and applications.


2014 ◽  
Vol 40 (8) ◽  
pp. 12623-12628 ◽  
Author(s):  
Ke Wang ◽  
Xueping Gan ◽  
Zhiyou Li ◽  
Dou Zhang ◽  
Kechao Zhou

2009 ◽  
Vol 9 (8) ◽  
pp. 786-794 ◽  
Author(s):  
Laurianne Timbart ◽  
M. Yat Tse ◽  
Stephen C. Pang ◽  
Oladunni Babasola ◽  
Brian G. Amsden

2008 ◽  
Vol 22 (18n19) ◽  
pp. 3237-3246 ◽  
Author(s):  
SOMAYE SAADAT ◽  
SAEED MALEKSAEEDI ◽  
MOHAMMAD HOSSEIN PAYDAR ◽  
HAFEZ AHMADI

Gelcasting process as a promising method for fabrication of reliable ceramics has been utilized to develop alumina-zirconia nanocomposites from nanosized powders. Sedimentation and viscosity measurement were performed to find the accurate dispersing condition for production of alumina-zirconia nanocomposite slurry with high solid loading and low viscosity. The gelcasting was accomplished by in situ polymerization of an acrylamide base monomer. The effects of solid loading, viscosity and deairing were also studied. Finally, crack and flaw free samples with relative densities of 99%, were achieved from the optimal slurry with 35vol. % solid loading, by performing sintering at 1600°C for 2 hours. SEM micrographs showed dense microstructure with fine and homogenous dispersion of zirconia phase in the alumina matrix.


2016 ◽  
Vol 256 ◽  
pp. 133-138 ◽  
Author(s):  
Marialaura Tocci ◽  
Christoph Zang ◽  
Ines Cadòrniga Zueco ◽  
Annalisa Pola ◽  
Michael Modigell

Rheological properties of liquid metals are difficult to investigate experimentally because of the extreme border conditions to consider. One difficulty is related to the low viscosity of liquid metals. Surface tension effects can cause forces that can be considerably higher than the viscous forces in the liquid metals. Evaluating the experimental data without considering these effects leads to an apparent shear thinning behavior of the material. In the present study, experiments were performed by means of a Searle rheometer changing the dimension of the measuring system with metals of high surface tension, as mercury and tin. It became evident that surface tension plays a significant role in the effects that falsify measurements at low shear rate. Conclusions can be drawn to what extent measurements of semi-solid metals are affected.


2016 ◽  
Vol 41 (6) ◽  
pp. 655-665 ◽  
Author(s):  
S Jager ◽  
R Balthazard ◽  
A Dahoun ◽  
E Mortier

SUMMARY Objectives: The objectives of this study were to determine the filler content, the surface microhardness (at baseline and after immersion in water for 2 years), and the rheological properties of various flowable resin composites. Methods: Three flowable resin composites (Grandioso Heavy Flow [GHF], Grandio Flow [GRF], Filtek Supreme XTE Flow [XTE]), one pit and fissure sealant resin composite (ClinPro [CLI]), and three experimental flowable resin composites with the same matrix and a variable filler content (EXPA, EXPB, EXPC) were tested. The filler content was determined by calcination. The Vickers surface microhardness was determined after polymerization and then after immersion in distilled water at 37°C for 7, 60, 180, 360, and 720 days. The rheological measurements were performed using a dynamic shear rheometer. Results: The determined filler contents differed from the manufacturers' data for all the materials. The materials with the highest filler content presented the highest microhardness, but filler content did not appear to be the only influencing parameter. With respect to the values recorded after photopolymerization, the values were maintained or increased after 720 days compared with the initial microhardness values, except for GHF. For the values measured after immersion for 7 days, an increase in microhardness was observed for all the materials over time. All the materials were non-Newtonian, with shear-thinning behavior. At all the shear speeds, GRF presented a lower viscosity to GHF and XTE. Conclusions: GRF presented a low viscosity before photopolymerization, associated with high filler content, thereby providing a good compromise between spreadability and mechanical properties after photopolymerization.


2020 ◽  
Vol 21 (2) ◽  
pp. 47-56
Author(s):  
Douaa Hussein Ali ◽  
Muhannad A.R. Mohammed

   This research studies the rheological properties ( plastic viscosity, yield point and apparent viscosity) of Non-Newtonian fluids under the effect of temperature using different chemical additives, such as (xanthan gum (xc-polymer), carboxyl methyl cellulose ( High and low viscosity ) ,polyacrylamide, polyvinyl alcohol, starch, Quebracho and Chrome Lignosulfonate). The samples were prepared by mixing 22.5g of bentonite with 350 ml of water and adding the additives in four different concentrations (3, 6, 9, 13) g by using Hamilton Beach mixer. The rheological properties of prepared samples were measured by using Fan viscometer model 8-speeds. All the samples were subjected to Bingham plastic model. The temperature range studied is from 50 to 200 °F. The results shows that the rheological properties (plastic viscosity, apparent viscosity and yield point) decreased as temperature increased for all prepared samples of non-Newtonian fluids.


2020 ◽  
Vol 23 (1) ◽  
pp. 68-80
Author(s):  
Douaa Hussein Ali ◽  
Muhannad A.R. Mohammed

This research study the rheological properties ( plastic viscosity, yield point and apparent viscosity) of non-Newtonian fluids under the addition of different chemical additives with different concentrations, such as (xanthan gum (xc-polymer) , carboxy methyl cellulose ( high and low viscosity ) ,polyacrylamide, polyvinyl alcohol, starch, quebracho, chrome lignosulfonate, and sodium chloride (NaCl). Fann viscometer model 800 with 8-speeds was used to measure the rheological properties of these samples, that have already been prepared. All samples were subjected to Bingham plastic model. It was concluded that the plastic viscosity, yield point and apparent viscosity should be increased with increasing the concentrations of (xanthan gum (xc-polymer) , carboxy methyl cellulose ( high and low viscosity ) ,polyacrylamide, polyvinyl alcohol, starch and sodium chloride (NaCl), while the opposite is true for quebracho, chrome lignosulfonate.


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