Firing Temperature Of Ceramics Research Articles

Luminescence dating and firing temperature determination of ancient ceramics fragments from the Tunata-hill site in the Churajon archaeological complex in Arequipa, Peru

Ancient pottery fragments from the Tunata-hill site in Churajon archaeological complex, Arequipa, Peru, were dated by means of luminescence techniques such as thermoluminescence (TL) and optically stimulated luminescence (OSL) in order to provide absolute chronology. For TL, additive and regenerative methods were performed. For OSL a regenerative method was carried out for IRSL dating. A rigorous description of the study area and its context has been made. The ages of the samples were found to be between 0.50 ± 0.06 ky and 0.49 ± 0.03 ky for TL methods, and 0.49 ± 0.02 ky for OSL methods. On average, the estimated age by TL and OSL techniques is 490 ± 70 yr (1600 AD and 1460 AD). This means that Churajon ceramics under study would belong to the Late periods which corresponds to the Inca region, and the North sub-region of the Late Churajon phase, and the beginning of European colonization in Peru. X-ray fluorescence technique (XRF) analysis has shown the main presence of Fe (39.5%), Si (30.0%), and Al (10.4%) in fine pottery powder. Furthermore, the electron paramagnetic resonance (EPR) technique was used to study the firing temperature using the iron signal (Fe3+) as a firing temperature reference. The firing temperature of ceramics was found to be around 550 ± 50 °C.

Clay 3D printing as a bio-design research tool: development of photosynthetic living building components

Within architecture, microalgae are employed to address sustainability issues and mitigate the impacts of anthropogenic carbon dioxide (CO2) emissions. This study proposes digital fabrication of ceramic ‘living’ building components as an investigative tool for design conditions. The health of the chlorophyte (green) microalga Chlorella vulgaris was monitored over two-week periods when immobilized in kappa carrageenan and clay binder-based hydrogels, and grown on a range of digitally fabricated ceramic components. The use of 3D printing is presented in relation to laboratory testing of controlled substrate variables including the impact of ceramic firing temperature, component wall thickness, three types of geometry for exploring cell growth, surface patterns to investigate cell migration, internal chamber subdivisions and clay type. The experiments reveal the benefits and limitations of creating micro-ecologies for algae growth through the introduction of geometry variation. In this study, the natural organismal sensing abilities are explored as a means for cell distribution.

Influence of the firing temperature on the dielectric properties of ceramics based on barium titanate

The object of the research is the firing temperature of ceramic materials based on barium titanate. In laboratory conditions, barium titanate was synthesized from raw materials of barium carbonate and titanium dioxide using ceramic technology, taking into account the stoichiometric composition of the compound. In order to study the effect of the firing temperature on the properties of the ceramic material, three temperatures were selected: 1270, 1300, and 1350 °C. The physical properties of the samples (imaginary density, water absorption, open porosity) were determined by the method of hydrostatic weighing in water. The samples were saturated with water after their preliminary evacuation. The dielectric characteristics of the obtained materials were measured on an E7-8CLR automated device (Ukraine) at a frequency of 1 kHz. The structural and morphological features of ceramics based on synthesized barium titanate were investigated by direct scanning electron microscopy and X-ray phase analysis. On the basis of the complex of studies carried out, the technological parameters of the production of ceramics were selected. Thus, the duration of grinding at the first and second stages is 10 and 30 minutes; moisture content of the press powder – 8 %; pressing pressure – 20 MPa; temperature of the first firing – 1000 °С; temperature of the second firing – 1350 °C. The regularity of the change in the dielectric constant on the firing temperature of ceramics based on barium titanate was established. The investigated samples, obtained according to the given technological regime, are characterized by the following indicators: dielectric constant – 259.9; open porosity – 0.02 %; water absorption – 0.01 %; imaginary density – 5.45 g/cm3. The resulting material can be used to create composite ceramic materials that protect biological and technical objects from the effects of electromagnetic radiation, and can also be used to create new functional materials for space, aerospace, electronic engineering and medicine.

Dating and determination of firing temperature of ancient potteries from Yumina archaeological site, Arequipa, Peru

Pottery fragments from the Yumina archaeological site, Arequipa, Peru, were dated by means of thermoluminescence (TL) and optically stimulated luminescence (OSL). Electron paramagnetic resonance (EPR) technique was used to study the firing temperature using the iron signal (Fe3+) as a firing temperature reference. The ages of the samples were found to be between 1190 ± 30 and 1240 ± 80 years (777 ± 80 and 827 ± 30 A.D.) determined by both techniques. The firing temperature of ceramics was found to be around 550 ± 50 °C. Our study, based on the combination of TL and OSL techniques to study Yumina archaeological site pottery, will be helpful for archaeologists in Peru. With the results of this investigation, we can understand the chronology and determine the areas of dispersion and density of the archaeological occupation in the Arequipa Valley. In addition, the calculated ages are consistent with the occupation period of the Yumina archaeological site estimated by stratigraphic analysis of the potteries.

Dating and determination of firing temperature of ancient potteries from São Paulo II archaeological site, Brazil by TL and EPR techniques

Pottery fragments from São Paulo II (SPII) archaeological site were dated by means of thermoluminescence (TL) and electron paramagnetic resonance (EPR). EPR was used to study the firing temperature using the iron signal (Fe 3+ ) as a firing temperature reference. The ages of the samples were found to be between 793 ± 102 and 1184 ± 142 a.C. The firing temperature of ceramics was found to be around 600–650 °C. Our study, based on the combination of EPR and TL techniques to study SPII archaeological site pottery, will be helpful for archaeologists in Brazil. With the results of this research, we can understand the chronology and determine areas of dispersion and density of archaeological occupation.

Resistance to Synthetic Seawater Aggression of Clay Ceramics Incorporated with an Ornamental Stone Residue

Clay ceramic materials exposed to a marine environment may be subjected to complete degradation due to the presence of chloride salts in the air. The exposition allows the chloride to penetrate in structural pores causing an internal expansion, which eventually split the ceramic apart. In open air, the solar radiation as well as the rain and wind contribute to accelerate the degradation process. In the present work the laboratory assisted degradation of clay ceramics incorporated with a granite residue from ornamental stone processing was evaluated by synthetic seawater aggression according to standard procedure. The amount of incorporated residues, up to 10 wt % and the ceramic firing temperature, up to 900°C, were variable conditions statistically analyzed by factorial planning. Degradation wetting-drying tests were conducted up to 6 months. The results showed that the linear shrinkage of the residue-free ceramics do not stabilize during the test period for any firing temperature. By contrast, the residue-incorporated ceramics tend to stabilize after 4 months. In addition, a decrease in water absorption and flexural strength was observed in same speciemens.