Unraveling the hardening mechanism during laser-induced slip casting of lithium aluminate-microsilica slurry

Ordered Ni3Fe crystals possess a LI2 type superlattice similar to the Cu3Au structure. The difference in slip behavior of the superlattice as compared with that of a disordered phase has been well established. Cottrell first postulated that the increase in resistance for slip in the superlattice structure is attributed to the presence of antiphase domain boundaries. Following Cottrell's domain hardening mechanism, numerous workers have proposed other refined models also involving the presence of domain boundaries. Using the anomalous X-ray diffraction technique, Davies and Stoloff have shown that the hardness of the Ni3Fe superlattice varies with the domain size. So far, no direct observation of antiphase domain boundaries in Ni3Fe has been reported. Because the atomic scattering factors of the elements in NijFe are so close, the superlattice reflections are not easily detected. Furthermore, the domain configurations in NioFe are thought to be independent of the crystallographic orientations.

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Study of the microstructure and particles of vanadium (III) oxide, vanadium (V) oxide and lithium aluminate powders

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2020-86-1-32-37 ◽

2020 ◽

Vol 86 (1) ◽

pp. 32-37

Author(s):

Valeria A. Brodskaya ◽

Oksana A. Molkova ◽

Kira B. Zhogova ◽

Inga V. Astakhova

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Vanadium Oxide ◽

Size Distribution ◽

Microstructural Analysis ◽

Coherent Scattering ◽

Powder Materials ◽

Lithium Aluminate ◽

Range Limit ◽

Oxide Particles

Powder materials are widely used in the manufacture of electrochemical elements of thermal chemical sources of current. Electrochemical behavior of the powders depends on the shape and size of their particles. The results of the study of the microstructure and particles of the powders of vanadium (III), (V) oxides and lithium aluminate obtained by transmission electron and atomic force microscopy, X-ray diffraction and gas adsorption analyses are presented. It is found that the sizes of vanadium (III) and vanadium (V) oxide particles range within 70 – 600 and 40 – 350 nm, respectively. The size of the coherent-scattering regions of the vanadium oxide particles lies in the lower range limit which can be attributed to small size of the structural elements (crystallites). An average volumetric-surface diameter calculated on the basis of the surface specific area is close to the upper range limit which can be explained by the partial agglomeration of the powder particles. Unlike the vanadium oxide particles, the range of the particle size distribution of the lithium aluminate powder is narrower — 50 – 110 nm. The values of crystallite sizes are close to the maximum of the particle size distribution. Microstructural analysis showed that the particles in the samples of vanadium oxides have a rounded (V2O3) or elongated (V2O5) shape; whereas the particles of lithium aluminate powder exhibit lamellar structure. At the same time, for different batches of the same material, the particle size distribution is similar, which indicates the reproducibility of the technologies for their manufacture. The data obtained can be used to control the constancy of the particle size distribution of powder materials.

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Optimization of Sintering Process of Alumina Ceramics Using Response Surface Methodology

Sustainability ◽

10.3390/su13126739 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6739

Author(s):

Darko Landek ◽

Lidija Ćurković ◽

Ivana Gabelica ◽

Mihone Kerolli Mustafa ◽

Irena Žmak

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Heating Rate ◽

Sintering Temperature ◽

Nonlinear Models ◽

Slip Casting ◽

Holding Time ◽

Alumina Ceramics ◽

Aqueous Suspensions ◽

Temperature Heating

In this work, alumina (Al2O3) ceramics were prepared using an environmentally friendly slip casting method. To this end, highly concentrated (70 wt.%) aqueous suspensions of alumina (Al2O3) were prepared with different amounts of the ammonium salt of a polycarboxylic acid, Dolapix CE 64, as an electrosteric dispersant. The stability of highly concentrated Al2O3 aqueous suspensions was monitored by viscosity measurements. Green bodies (ceramics before sintering) were obtained by pouring the stable Al2O3 aqueous suspensions into dry porous plaster molds. The obtained Al2O3 ceramic green bodies were sintered in the electric furnace. Analysis of the effect of three sintering parameters (sintering temperature, heating rate and holding time) on the density of alumina ceramics was performed using the response surface methodology (RSM), based on experimental data obtained according to Box–Behnken experimental design, using the software Design-Expert. From the statistical analysis, linear and nonlinear models with added first-order interaction were developed for prediction and optimization of density-dependent variables: sintering temperature, heating rate and holding time.

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Processing of concentrated aqueous fluorapatite suspensions by slip casting

Journal of Materials Science ◽

10.1007/s10853-011-5443-6 ◽

2011 ◽

Vol 46 (15) ◽

pp. 5117-5128 ◽

Cited By ~ 10

Author(s):

María P. Albano ◽

Liliana B. Garrido

Keyword(s):

Slip Casting

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Environmental footprint as a criterion in the ZTA composites forming process via centrifugal slip casting

Ceramics International ◽

10.1016/j.ceramint.2021.03.121 ◽

2021 ◽

Author(s):

Justyna Zygmuntowicz ◽

Justyna Tomaszewska ◽

Radosław Żurowski ◽

Marcin Wachowski ◽

Ireneusz Szachogłuchowicz ◽

...

Keyword(s):

Slip Casting ◽

Environmental Footprint ◽

Forming Process

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Preparation of highly concentrated aqueous hydroxyapatite suspensions for slip casting

Journal of Materials Science ◽

10.1007/s10853-005-0890-6 ◽

2005 ◽

Vol 40 (17) ◽

pp. 4619-4623 ◽

Cited By ~ 11

Author(s):

Z. Sadeghian ◽

J. G. Heinrich ◽

F. Moztarzadeh

Keyword(s):

Slip Casting

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Gray Phonon Transport Prediction of Thermal Conductivity in Lithium Aluminate with Higher-Order Finite Elements on Meshes with Curved Surfaces

Journal of Computational and Theoretical Transport ◽

10.1080/23324309.2021.1900258 ◽

2021 ◽

pp. 1-25

Author(s):

Nicholas H. Whitman ◽

Todd S. Palmer ◽

P. Alex Greaney ◽

S. Aria Hosseini ◽

Douglas E. Burkes ◽

...

Keyword(s):

Thermal Conductivity ◽

Finite Elements ◽

Phonon Transport ◽

Higher Order ◽

Curved Surfaces ◽

Lithium Aluminate ◽

Higher Order Finite Elements ◽

Transport Prediction

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Sintering Behavior, Thermal Expansion, and Environmental Impacts Accompanying Materials of the Al2O3/ZrO2 System Fabricated via Slip Casting

Materials ◽

10.3390/ma14123365 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3365

Author(s):

Justyna Zygmuntowicz ◽

Magdalena Gizowska ◽

Justyna Tomaszewska ◽

Paulina Piotrkiewicz ◽

Radosław Żurowski ◽

...

Keyword(s):

Thermal Expansion ◽

Life Cycle ◽

Coefficient Of Thermal Expansion ◽

Raw Materials ◽

Slip Casting ◽

Ceramic Materials ◽

Sintering Behavior ◽

Environmental Loads ◽

Practical Applications ◽

Technical Ceramics

This work focuses on research on obtaining and characterizing Al2O3/ZrO2 materials formed via slip casting method. The main emphasis in the research was placed on environmental aspects and those related to the practical use of ceramic materials. The goal was to analyze the environmental loads associated with the manufacturing of Al2O3/ZrO2 composites, as well as to determine the coefficient of thermal expansion of the obtained materials, classified as technical ceramics. This parameter is crucial in terms of their practical applications in high-temperature working conditions, e.g., as parts of industrial machines. The study reports on the four series of Al2O3/ZrO2 materials differing in the volume content of ZrO2. The sintering process was preceded by thermogravimetric measurements. The fabricated and sintered materials were characterized by dilatometric study, scanning electron microscopy, X-ray diffraction, and stereological analysis. Further, life cycle assessment was supplied. Based on dilatometric tests, it was observed that Al2O3/ZrO2 composites show a higher coefficient of thermal expansion than that resulting from the content of individual phases. The results of the life cycle analysis showed that the environmental loads (carbon footprint) resulting from the acquisition and processing of raw materials necessary for the production of sinters from Al2O3 and ZrO2 are comparable to those associated with the production of plastic products such as polypropylene or polyvinyl chloride.

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