Baryshok. Enriching colour range of ceramic shapes on clay-based materials of low quality

Introduction. This article discusses the possibility of expanding the colour palette of a ceramic shard. Due to the shortage of high-quality clay raw materials for the manufacture of plastic molded facing bricks, the problem of manufacturing ceramic wall materials by semi-dry pressing from low-quality clay rocks is urgent.Materials and methods. The main raw material was non-caking clay raw material with a low content of clay and a high content of silt particles. Some corrective additives were used to expand the colour palette of ceramic bricks. In the article, the authors used both standard methods for determining the physical and mechanical properties and modern methods for studying the phase composition of materials.Results. The possibility of enriching the colour range of a ceramic shard based on non-sintered clay raw materials has been experimentally confirmed, provided that the mixture contains flux additives. When receiving products with a clarified shard, light-colored flutes should be used.Conclusion. The possibility of enriching the colour range of a ceramic cap by adding white-burning clay, introducing bleaching and chromophore additives and technogenic products has been established. Due to the differences in the chemical composition of clay raw materials from individual deposits, an individual approach to each of them is required.

Investigations of the relics and altar materials relating to the apostles St James and St Philip at the Basilica dei Santi XII Apostoli in Rome

Two types of materials were sampled as part of an investigation of the relics of the Holy Catholic Church of the Apostles St Philip and St James in the Basilica dei Santi Apostoli in Rome: bone- and mummy-materials and architectural samples. The analyses encompassed radiocarbon dating, thermoluminescence dating, gas and liquid chromatographic separation with mass spectrometric detection, X-Ray fluorescence, X-Ray diffraction, inductively coupled plasma mass spectrometry, Raman spectroscopy, and Fourier transform infrared spectroscopy. The results show that the samples were subjected to a number of conservational and exhibition-related treatments. The alleged femoral bone of St James was dated between AD 214 and 340 (2σ confidence), which shows that this cannot be the bone of St James. An encrustation found in a canal in the reliquary in the high altar construction showed the presence of heavily oxidized rapeseed oil, which was radiocarbon dated between AD 267 and 539 (2σ confidence), and a ceramic shard also found in the high altar construction was TL-dated to AD 314–746 (2σ confidence). The two latter dates are consistent with a translation of the relics following the erection of the church at the time of Pope Pelagius I in AD 556–561.

The relationship of phase and chemical compositions of a durable ceramic material of the fortification wall of the city of Thessaloniki (Greece) age more than 1000 years

A ceramic material with an age of more than 1000 years has been studied. Plinth was used as a ceramic material for the construction of the fortress wall. In addition, the element analysis determined an increased content of carbon in the samples - 9,50 %. Increased carbon content in inclusions indicates the introduction of fuel into the raw material. The introduction of fuel into the raw material not only increases the porosity of the products, but also contributes to the uniform sintering of the ceramic shard and with an increased content of alkali oxides (R2O > 4 %), the formation of a glass phase up to 1000 oC.

Building Ceramics Based on Carbonate-Containing Raw Materials

The results of the production of wall ceramics based on the composition of low-melting argillaceous raw materials - loam and fuel slag in an amount of 10-30% by the method of semi-dry pressing are presented. Pre-baking and calcining properties of clay materials are investigated, the results of x-ray diffraction analysis and differential thermal analysis of the raw materials are given. The results obtained by the method of mathematical planning of the experiment made it possible to develop a model of ceramic bricks of the racial composition, to construct empirical dependencies in the system «technogenic product-technological factor-property» and to establish the influence of the addition of fuel slag on the basic physical and mechanical properties of wall ceramics: strength, density, water absorption , shrinkage. The results of studies of the modifying role of the container glass in the processes of pyrogenic synthesis of clay-slag masses and its effect on the preparation of a ceramic shard of a racial composition with the required properties are shown.

Activated ceramic compositions with the addition of serpentinite

The article describes the loam of the Kubekovsky deposit of the Krasnoyarsk Territory, which is widely used in the production of ceramic bricks in factories that produce wall materials. In the studies described in the article, mechanoactivation and modification were used to improve its technological and physico-mechanical characteristics. Mechanoactivation was carried out in a hydrodynamic dispersant. As the additive-modifier used waste stoneplant serpentinites of the Perevalnoye deposit. The effect of the additive-modifier on the properties of ceramic compositions is shown. It is shown that a small amount of serpentinite up to three percent -significantly increases the compressive strength of fired ceramic samples.If the composition has an additive of more than three percent, a decrease in strength characteristics is observed, this is related, probably due to the fact that most of the magnesium oxide remains unreacted. White inclusions areobserved visually in the structure of calcined samples throughout the volume. The combined effect of mechanoactivation and modification is shown, which makes it possible to improve the technological and physicomechanical characteristics of the ceramic shard. The results of electron microscopy are presented, suggesting that the microstructure of a ceramic shard activated with the addition of serpentinite contains moremullite-rich mixed crystals, as well as devitrified areas. Inclusions of magnesium oxide are not observed. Magnesium oxide in the ceramiccomposition serves as a primer capable of making the melt more liquid,accelerating its devitrification.

Effects of waterjet cutting waste addition on properties of building ceramics

The purpose of the paper is to investigate the possibility of using wastes of waterjet metal cutting in the manufacture of building ceramics. A complex study of the composition and properties of the abrasive and hydroabrasive cutting wastes was carried out. The behavior of waste in the composition of the ceramic mass and the ceramic body was investigated. Positive results of the effect of addition of waste on the properties of ceramics were obtained on two types of polymineralic argillaceous raw materials: increase of strength at the optimum content of waste in the mixture, reduction of air and fire shrinkage in all compositions with waste content, possibility of varying the color of products, etc. The similarity of the chemical composition of argillaceous raw materials and wastes was established: oxides of iron, silicon and aluminum are predominant. Electron microscope research has demonstrated that the introduction of waste modifies the structure of the ceramic shard, but does not affect its uniformity. The obtained results allowed to draw conclusions about the possible use of wastes of waterjet metal cutting in the production of ceramics: as a fluxing agent – flux, component for volumetric staining, thinning agent.