Using the methods of thermodynamic analysis to optimize the composition of high-refractory cements in the CaO-Al2O3-MgO system

Саркисов, П. Д.; Sivkov, S. P.; Кузнецова, Т. В.; Мешалкин, В. П.

doi:10.1134/s0040579513010077

Cited by 3 publications

(3 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At this stage, the phases start to gradually melt and liquefy followed by the damage of the crystal ordering forms amorphous structure. The CaO-MgO-Al 2 O 3 system composition fired at 1,400 °C [28]. By the projection of the studied composition mixtures on this diagram, it will be located in the range of the optimal composition; however, there is a little increase of the MgO content.…”

Section: Characterizations (1) Phase Composition and Microstructurementioning

confidence: 93%

“…The temperature of the specimens was kept constant at a rate of 4 o C from room temperature up to the maximum firing temperature. The sintering temperatures of each batch were proposed based on the phase diagram [28][29][30] and after testing experimentally. One of these temperatures is the temperature after which the ceramic object melts.…”

Section: Specimens Preparationmentioning

confidence: 99%

See 1 more Smart Citation

Bioactivity Investigations with Calcia Magnesia Based Composites

Ewais¹,

Moustafa²,

Pardun³

et al. 2015

JMSE-A

View full text Add to dashboard Cite

Abstract:The bioactivity and physico-mechanical properties of calcia magnesia based composites developed in this study were investigated. Different composite mixtures containing calcia-magnesia have been processed with the addition of alumina, silica or zircon. These system powders were formed and fired at two different temperatures. The produced composites were characterized by means of X-ray diffraction, SEM (scanning electron microscope) equipped with EDS (energy dispersive X-ray spectrometry), density and apparent porosity measurements, mechanical testing and in-vitro evaluation in a SBF (simulated body fluid) solution. The compositions termed "I", "II" and "III" gave clear tendency towards the formation-ability of HA (hydroxyapatite). Composite "1" gave cubic and spindle HA crystallite, while composites "II" and "III" fired at 1,300 and 1,400 °C formed typically "cauliflower" morphology and their evaluated physico-mechanical properties are similar to the properties of human cortical bone. Thus, composites "II" and "III" might be a promising bone implant materials. Beside the bioactivitiy of composite "I", it also contains highly CA (cementing phase) and MA (bioinert) phases, therefore, it might be nominated as a promising bioceramic material especially for different purposes such as scaffold, bone replacement, bone repair and coating.

show abstract

Section: Characterizations (1) Phase Composition and Microstructurementioning

confidence: 93%

Section: Specimens Preparationmentioning

confidence: 99%

Bioactivity Investigations with Calcia Magnesia Based Composites

Ewais¹,

Moustafa²,

Pardun³

et al. 2015

JMSE-A

View full text Add to dashboard Cite

show abstract

“…However, during recent years the ternary system has seen a revival of interest due to applications in the fields of slag research for secondary refining processes in metallurgy, refractories or as host materials for luminescence applications . Aside from experimental studies, thermodynamic assessments using the Calphad technique have also been employed . Although, as pointed out by Hallstedt, the computational results have to be treated with care as long as there is a lack of data on solid‐phase relations.…”

Section: Introductionmentioning

confidence: 99%

Structural studies on Ca₃Al₄MgO₁₀ (C₃A₂M)—A ternary phase in the system CaO–Al₂O₃–MgO

et al. 2018

View full text Add to dashboard Cite

In a sequence of temperature‐dependent solid‐state reactions in the system CaO–Al2O3–MgO the formation of the ternary phase Ca3Al4MgO10 or C3A2M has been studied. Whereas the compound could not be prepared at 1200°C, a yield of 85 wt.‐% of Ca3Al4MgO10 was obtained at 1320°C (incongruent melting point: 1330°C). Powder diffraction data compare well with results of previous investigations from the 1960s. Single crystals of Ca3Al4MgO10 could be retrieved from the sinter‐pellets. Basic crystallographic data are as follows: orthorhombic symmetry, space group Pbcm, a = 5.14073(8), b = 16.7576(2), c = 10.70977(16) Å, V = 922.61(2) Å3, Z = 4. Using synchrotron diffraction data it was possible to solve the crystal structure. Least‐squares refinements resulted in a residual of R(|F|) = 0.021 for 1000 independent observed reflections with I > 2σ(I) and 97 parameters. The structure contains [TO4]‐tetrahedra (T=Al,Mg) forming a three‐dimensional (3‐D) framework whose topological characteristics have been determined. Al‐Mg distributions on the different T‐sites have been studied. The calcium cations are located in voids of the network. More than 50 years after its first observation our investigation clarifies the crystal structure of a compound belonging to a system that is of relevance for several fields of materials science.

show abstract

Thermodynamic Analysis of Hydration Processes of Calcium Aluminoferrites

Rahimbaev

Onoprienko

Rahimbaev³

2021

Bulletin of Belgorod State Technological University Named After. V. G. Shukhov

View full text Add to dashboard Cite

The processes of hydration and hydrate phase formation of calcium aluminoferrites are insufficiently covered in the technical literature. Thermodynamic analysis of the hydration processes of calcium aluminoferrite of 4CaO·Al2O3·Fe2O3 is difficult due to the unreliability of the initial data for hydration products. The question of the basicity of calcium hydroferrites requires clarification. There is insufficient data on the justification of the method of calculating the thermodynamic properties of hydroferrite -∆G0298, - ∆H0298 and c(T), verification of their results, the mechanism of formation of the complex anion Fe(OH)4- and its stability in the liquid phase of hydrating C4AF. The hydration of 4CaO·Al2O3·Fe2O3 with the formation of 2CaO·Al2O3·8H2O as hydrate phases is considered. The energy of hydrogen bonds between the layers of Ca(OH)2, Al2(OH)3 and Fe(OH)3, from which the hexagonal layers of these complex calcium, aluminum and iron hydroxides are composed, is compared. It is shown that the values of ∆G0298 and ∆H0298 2CaO·Fe2O3·8H2O, which are equal to -937.2 and -1082.3 kcal/mol, respectively, are not consistent with experimental data on the solubility of C2FH8 and the specific heat release during C4AF hydration (100-115 kcal/g). Values for C2FH8, ∆G0298= -933, ∆H0298 = -1072 kcal/mol are recommended. It is shown that the formation of Fe(OH)3 hydroxide in the amorphous state, rather than the Fe(OH)4 ion, is preferable as an intermediate product of C4AF hydration.

show abstract

Using the methods of thermodynamic analysis to optimize the composition of high-refractory cements in the CaO-Al2O3-MgO system

Cited by 3 publications

References 2 publications

Bioactivity Investigations with Calcia Magnesia Based Composites

Bioactivity Investigations with Calcia Magnesia Based Composites

Structural studies on Ca₃Al₄MgO₁₀ (C₃A₂M)—A ternary phase in the system CaO–Al₂O₃–MgO

Thermodynamic Analysis of Hydration Processes of Calcium Aluminoferrites

Contact Info

Product

Resources

About

Using the methods of thermodynamic analysis to optimize the composition of high-refractory cements in the CaO-Al2O3-MgO system

Cited by 3 publications

References 2 publications

Bioactivity Investigations with Calcia Magnesia Based Composites

Bioactivity Investigations with Calcia Magnesia Based Composites

Structural studies on Ca3Al4MgO10 (C3A2M)—A ternary phase in the system CaO–Al2O3–MgO

Thermodynamic Analysis of Hydration Processes of Calcium Aluminoferrites

Contact Info

Product

Resources

About

Structural studies on Ca₃Al₄MgO₁₀ (C₃A₂M)—A ternary phase in the system CaO–Al₂O₃–MgO