Porcelain Samples Research Articles

Investigation of the properties of aluminous porcelain samples of a long-rod insulator subjected to high DC voltage

Investigation of the properties of aluminous porcelain samples of a long-rod insulator subjected to high DC voltage

Study on the Influence of Calcination Temperature of Iron Vitriol on the Coloration of Ancient Chinese Traditional Iron Red Overglaze Color.

Iron red, a traditional Jingdezhen overglaze color, is primarily colored with iron oxide (Fe2O3). In traditional processes, the main ingredient for the iron red overglaze color, raw iron red, is produced by calcining iron vitriol (FeSO4·7H2O). Analysis of ancient iron red porcelain samples indicates that the coloration is unstable, ranging from bright red to dark red and occasionally to black. Addressing this, the present study, from a ceramic technology standpoint, conducts a series of calcination experiments on industrial iron vitriol at varying temperatures. Utilizing methodologies such as differential scanning calorimetry-thermogravimetry (DSC-TG), Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy with X-ray energy dispersive spectrometry (SEM-EDS), and optical microscopy (OM), this research scientifically explores the impact of iron vitriol's calcination temperature on the coloration of traditional Jingdezhen iron red overglaze color. The findings indicate that from room temperature to 550 °C, the dehydration of iron vitriol resulted in the formation of Fe2(SO4)3 and a minimal amount of α-Fe2O3, rendering the iron red overglaze color a yellowish-red shade. At 650 °C, the coexistence of Fe2(SO4)3 and α-Fe2O3 imparted a brick-red color to the iron red. As the temperature was elevated to 700 °C, the desulfurization of Fe2(SO4)3 produced α-Fe2O3, transitioning the iron red to an orange red. With further temperature increase to 750 °C, the particle size of α-Fe2O3 grew and the crystal reflectivity decreased, resulting in a purplish-red hue. Throughout this stage, the powder remained in a single α-Fe2O3 phase. Upon further heating to 800 °C, the crystallinity of α-Fe2O3 enhanced, giving the iron red overglaze color a dark red or even black appearance.

Exploring Digital Gingival Shade Matching in Students.

To study the degree of accuracy in gingival shade matching of undergraduate students using a computer application. In total, 76 undergraduate dental students' gingival shade selection abilities were evaluated using an in-house developed computer application. A total of 15 intraoral gingival photographs and 21 pink gingival color porcelain samples were used. The environmental conditions were standardized, and no time limit was set for answering in the computer application. Fourteen gingival color samples (66.6%) were not useful for representing the studied gingival shades. Not all natural gingival colors studied were represented within the 50.50% acceptability limits of the pink samples. There were no statistically significant differences between men and women in terms of "hit" percentages. The highest correlation coefficient (in absolute value) was for the L* coordinate (the darker the gingiva in the picture, the higher the hit rate for choosing the "ideal" shade tab); however, none of the linear correlation coefficients were statistically significant. Not all colors provided in the pink ceramic system were useful for subjective gingival selection. There were no statistically significant differences between male and female dental students in gingival color perception. The L* coordinate was the only one that influenced the correct perception of gingival color by dental students, and it did so more in women than in men.

Performance enhancing of porcelain insulators using low cost micro additives

Porcelain have been widely utilized in electrical power system. The enhancement of its properties has positively influenced its behavior thence on overall power system. Nano/Micro technologies are influential field used for developing different characteristics of porcelain insulators. In this work, three weight percentages of fly ash micro-particles were admixed to neat porcelain. Characterization and morphological features for prepared samples were scrutinized using XRD and SEM. BDV, relative permittivity, and dissipation factor were measured. Moreover, porosity, bulk density, and water absorption were measured. COMSOL Software was used to simulate the electric field distribution on the samples. This study indicated, fly ash promoted the electrical characteristics of porcelain. Inclusion of 6 % fly ash along the porcelain sample increases BDV from 22.5 kV to 56.7 kV. The presence of fly ash inside porcelain not only decreased relative permittivity but also dissipation factor. The optimum sintering temperature gives lowest porosity and highest bulk density was 1200 °C.

Effect of temperature and glass content on crystalline phases in porcelain sintered with recovered automotive glass

In the pursuit of sustainable porcelain production, this research examines the potential of using recovered automotive glass as a substitute for traditional feldspar, specifically feldspar imported from Spain. Porcelain samples were sintered at different temperatures and with varied proportions of automotive glass. The crystalline phases formed post-sintering were determined through X-ray diffraction and quantified by dissolving the porcelain in concentrated hydrofluoric acid. Results revealed that the inclusion of automotive glass, owing to its dissolved oxide content, accelerated the porcelain melting process and led to an increase in the vitreous phase. Notably, anorthite phases became dominant and mullite formation was evident at 1100 °C, stabilizing in samples G00 and G10, and then increasing at 1200 °C due to the emergence of secondary mullite. This secondary mullite forms from the residual silica after the primary mullite formation and the aluminium in the feldspars, which is about 17 %. For samples G20 and G30, only primary mullite was observed due to the decreased aluminium content resultant from feldspar replacement by glass. These findings underscore the viability of automotive glass in porcelain production, providing a sustainable and effective alternative to feldspar.

Effectiveness of Porcelain Polishing Methods on the Roughness and Color Stability of CAD-CAM Ceramics after Orthodontic Bracket Debonding.

Increased utilization of all ceramic restorations for aesthetic consideration in combination with routine adult orthodontic practice has led to numerous clinical challenges. Obtaining adequate bond strength between the orthodontic bracket and all-ceramic restoration and damage to the ceramic surface during the bracket debonding procedure needs to be better understood. This study analyzed the surface texture and color change of glazed and bracket-debonded ceramic CAD-CAM materials and the efficiency of porcelain polishing systems in restoring surface morphology and color. A total of 30 rectangular test specimens from each lithium disilicate CAD (LD-CAD), polymer-infiltrated ceramic (PICN), zirconia-reinforced lithium silicate glass ceramic (ZLS), and 5YTZP zirconia (5YZP) were prepared. The ceramic samples were embedded within acrylic resin, and baseline surface roughness and color were recorded using an optical profilometer and a reflected color spectrophotometer. The porcelain samples were bonded with lower incisor ceramic brackets. The samples were thermocycled 2000 times between 5 and 55 °C. Afterward, the brackets were peeled with bracket-removing pliers. The resin adhesive from the debonded surface was eliminated with tungsten carbide bur, and samples were randomly divided into three subgroups of (n = 10) to be polished with Diapol-twist (DT), a Keramik-Politur 4313B Komet polishing kit (KK), and a Horico diamond polisher (HDP). The polished surface roughness and color were recorded. The data were statistically analyzed using a two-way analysis of variance at p < 0.05. The debonded porcelain surfaces across the groups displayed significantly higher mean surface roughness (Ra) compared to glazed surfaces. The debonded 5YZP showed the least Ra at 0.661 (0.09), while the highest Ra was recorded by PICN at 4.057 (0.82). All of the polishing systems evaluated in the study significantly reduced the surface roughness. However, they were unsuccessful in regaining the surface topography of the glazed surface. The flexible discs (DT) produced the smoothest surface, followed by the diamond-impregnated rubber points (KK). Unpolished porcelain surfaces had a discernable mean color difference from glazed surfaces. Polished surfaces from the different polishing systems among the all-ceramic groups achieved a clinically acceptable mean color difference. Polishing debonded rough porcelain surfaces is imperative, and flexible discs performed better in all of the tested CAD-CAM ceramic materials.

The investigation of the physical properties of an electrical porcelain insulator manufactured from locally sourced materials

Abstract The work aims to evaluate the effect of temperature and composition on the physical properties of ceramic electrical porcelain insulators, produced from locally sourced materials in Nigeria. The basic raw materials of triaxial porcelain (Kaolin, feldspar, and quartz) were pulverized, milled for 22 h, and sieved using a 200 μm mesh size. The chemical composition and characterization of the raw materials were obtained using X-ray diffraction (XRD) and X-ray fluorescence (XRF) analysis. The mixtures were formulated using sodium silicate as a deflocculant to help produce the ceramic porcelain samples. The green samples were weighed and fired at temperatures of 1200 °C and 1250 °C. The samples were subjected to 1 h of boiling plus 2 h of soaking. The slip casting technique was used in the production of porcelain insulators. The linear shrinkage, water absorbance, apparent porosity, and bulk density were measured and studied as a function of firing temperature. The apparent porosity and water absorption decreased as the firing temperature increased. The bulk density increased gradually from 1200 °C to 1250 °C and the percentage of moisture remained fairly unaffected by the temperature increase. The linear shrinkage was also found to increase as the firing temperature increased. Despite having the same composition, the average physical properties of the locally manufactured insulators revealed that those manufactured at higher temperatures provided a better insulating effect than those manufactured at lower temperatures. In other words, it shows that excellent ceramic porcelain insulators can be manufactured from locally sourced materials using the appropriate composition and firing temperature.

Influence of Multiple Firings on the Color Stability and Surface Roughness of Gingival Pink Feldspathic Ceramic

The present study was aimed at analyzing the impact of repeated firings on the color stability and surface roughness (Ra) of gingival pink feldspathic porcelain. Twenty specimens (n = 20) were prepared, and repeated firings were carried out. These samples were equally and randomly divided into two groups (n = 10) to assess the color change (ΔE), using a spectrophotometer and Ra using a non-contact profilometer. The ΔE was calculated after the third, fifth, and seventh firings, whereas the Ra was assessed after the first, third, fifth, and seventh firings. The greatest ∆E was observed after the seventh firing (6.86), followed by the fifth firing (3.93). The lowest ∆E was seen after the third firing (2.61). All the inter-group comparisons were statistically significant (p &lt; 0.01). The change in color of gingival pink feldspathic porcelain samples observed after multiple firings could be attributed to pigments in this material becoming unstable, and the possible change in the crystal orientation with increased firings. The highest Ra was observed for the samples after the first firing (1.130 μm), followed by the third firing (0.617 μm) and fifth firing (0.477 μm). The lowest Ra values were seen for the samples after the seventh firing (0.425 μm). All the inter-group comparisons were statistically significant (p &lt; 0.01), except when the Ra values of samples after the fifth and seventh firing were compared (p &gt; 0.01). The decreased Ra could be attributed to the melting of glaze with increased firings, which could have filled the gaps on the porcelain’s surface making it less rough. The present study demonstrated that an increase in repeated firings resulted in an increase in the ∆E values and a decrease in the Ra values of gingival pink feldspathic porcelain samples. The greatest increase in ∆E and the highest reduction in Ra values were noticed after the seventh firing. Future studies, including other parameters (variable thickness of ceramic and firing temperatures), should be conducted to study the impact of repeated firings on the color stability and roughness of gingival pink feldspathic porcelain.

Pengaruh Tingkat Profitabilitas Terhadap CSR (Studi Empiris Perusahaan Manufaktur Sektor Semen, Keramik, Porselen Dan Kaca Yang Terdaftar Di BEI Tahun 2018-2020)

This study was conducted with the aim of knowing whether there is an influence on the profitability of manufacturing companies in the cement, ceramic, porcelain, and glass sectors listed on the Indonesia Stock Exchange in 2018-2020 on Corporate Social Responsibility. The company's profitability can be affected by circumstances such as the Covid-19 pandemic because it disrupts the company's operations so that many companies experience a decline in profits during the pandemic. Profitability measurement is carried out using financial ratios, namely Net Profit Margin (NPM), while Corporate Social Responsibility is measured using the Corporate Social Responsibility Disclosure Index (CSRDI). This study uses 35 samples of cement, ceramic, porcelain, and glass manufacturing companies listed on the IDX from 2018 to 2020 where the type of data used is secondary data obtained from the company's financial statements. The test for this hypothesis is multiple linear regression using SPSS version 22. The results show that profitability has a positive effect on Corporate Social Responsibility. In addition to profitability, there is also the size of the company which has a positive influence on Corporate Social Responsibility.

Quantitative analysis the similarity of appearance color of white porcelain in xing and ding kilns based on chromaticity

As the famous white porcelain kilns in ancient China, Xing Kiln and Ding Kiln have similarity appearance because they have similarities of modeling and firing methods of utensils during their development, but their colors are still described through eye observation, and no scientific comparative analysis has been conducted. Colorimetry has the advantage of quantitative analysis in studying the color of ceramic compared with the traditional naked eye observation description. Therefore, the representative samples of white porcelain of Xing and Ding Kilns from Tang Dynasty to Jin Dynasty were selected for colorimetric analysis with CIE. The color similarity and changes of the two kilns in different times were analyzed, the results showed that appearance color of the samples from the Xing and Ding Kilns are similar to that observed by the naked eye. Moreover, the results show two different color types of the samples in the Tang dynasty from both Ding and Xing kilns. Type II is typical of northern white porcelain as previous studies, but type I is closer to greenish white porcelain. They were found, and this was supposed to be the result of Ding Kiln’s imitation of the Xing Kiln in its early days. However, since Xing Kiln has been discontinued in Song Dynasty, only type II was found in the white porcelain of Xing Kiln and Ding Kiln after Tang Dynasty.

Partial substitution of feldspar by alkaline-rich materials in the electrical porcelain insulator for reduction of processing temperature

Porcelain is the most widely used overhead power-line insulator. The demands for porcelain insulators have increased dramatically owing to a sharp increase in the electric power demand and supply. Usually, porcelain production demands high sintering temperatures. Herein, an electrical porcelain insulator was produced from Bombowha clay and Arero quartz and partially replaced feldspar with sodium carbonate at a reduced processing temperature. The porcelain samples were prepared by fixing the clay and quartz amount 45 and 10 wt%, respectively, and the portion of feldspar was replaced by 5, 7.5, and 10 wt% of alkaline-rich sodium carbonate. The desired composition was milled, shaped, and finally sintered at 1000, 1100, and 1200 °C. The XRD and SEM results show the early formation of quartz and mullite phases at 1000 °C, which determine the mechanical and dielectric strengths of the porcelains. The dielectric strength of the samples increases with increasing the alkaline-rich sodium carbonate content owing to the vitrification and needle-shaped mullite formation. The porcelain sample with 10 wt% of Na2CO3 content and a sintering temperature of 1200 °C has an optimum dielectric strength of 7.60 kV mm−1.

Evaluation of morphology, hardness and structure of laser exposed dental porcelain

The surface management of dental porcelain for different dental applications is an important procedure in dentistry. On one hand, we need rough and course surfaces for bonding purposes, and on the other hand, the surface of the dental porcelain needs to be glazed to acquire the best aesthetic appearance and strength. As pores and voids scatter the light and decrease the translucency and may initiate chipping off the material from high-stress points. Mainly the consolidation of the porcelain and elimination of porosity is achieved by sintering. The reduction of porosity is more dependent upon temperature than on time. Therefore, it is possible to attain optimum glazing at a comparatively faster rate by using energy delivery through laser irradiation. In this study, Nd: YAG laser is irradiated on porcelain samples in pellet form. After laser irradiation, a glazed and mechanically improved porcelain surface is obtained with no considerable change in its microstructure.

The mechanism of “flint red” and its relationship with celadon glaze color

"Flint red" is the red narrow band found in the exposed body of porcelain, which is a common phenomenon in ancient porcelain. Some experts believe that flint red is an important symbol for judging the age of ancient ceramics. This paper takes sky-green Yaozhou porcelain as the example, and successfully fired samples of Yaozhou porcelain with flint red, and reveals the formation mechanism of flint red. This study uses XRF (X-ray fluorescence), XRD (X-ray diffraction), SEM (Scanning electron microscope) and non-contact imaging spectrophotometer analysis to discover for the first time that during the reduction process, the iron of the glaze migrates to the body with the melt in the gas phase, and the flint red is a hematite thin film formed on the body after being oxidized for the second time during the cooling process of the kiln. The influence of the redox atmosphere and placement mode of ceramics on flint red were studied. The relationship between flint red and the degree of color reduction of celadon glaze surface was discussed. In addition, the growth method of hematite film is enlightening for the preparation of anticorrosive coatings on steel products, and has broad application prospects.

Effect of firing temperature on the interface between 3Y-TZP zirconia and porcelain.

The purpose of this study is to clarify the porcelain firing temperature conditions that give strongest bonding strength of porcelain to zirconia to manufacture all-ceramic fixed dental prostheses (FDPs) with excellent long-term stability. Opaque porcelain samples (8.0 × 3.0 × 1.2 mm) were placed in the center of zirconia plates (25.0 × 3.0 × 0.5 mm) and fired at temperatures of 950°C, 1,050°C, 1,100°C, and 1,150°C. Schwickerath crack initiation tests, elemental analyses, and morphological changes of the samples were compared. There was no difference in the bonding strength among all the groups of porcelain fired at different temperatures. Elemental analysis of Si and O2 at the interface between the zirconia and porcelain were observed in the 950°C, 1,050°C, and 1,100°C groups. No silicon was found in the 1,150°C group by elemental analysis, and the zirconia plate where the porcelain sample was placed had irregular shape changes. It is suggested that silicon is also involved in chemical bonds due to firing at high temperatures.

Determination of Shear Bond Strength of Nanocomposite to Porcelain and Metal Alloy

Objective: To compare porcelain and metal repair done with both nanocomposite and conventional composite. Material and Methods: A total of 30 cylinders were fabricated from Porcelain (I), Porcelain fused to metal (II), and metal (III) substrate each. Control group (A) was bonded with conventional micro-hybrid composite and experimental group (B) was bonded with nanocomposite in a 2 mm thickness. All specimens were thermocycled and stored in distilled water at 37 °C for 7 days. A universal testing machine was used to measure the Shear bond strength (SBS). The difference between bond strengths of the groups was compared using an independent t-test. Results: In all three groups, the SBS was higher in the experimental group as compared to the control group. The use of nanocomposite of metal alloy presented maximum shear bond strength, followed by samples of porcelain fused to metal and finally porcelain, showing the lowest values of SBS. Conclusion: Porcelain and alloys bonded with nanocomposite exhibit enhanced adhesiveness as well as aesthetic and mechanical properties. This subsequently would translate into providing higher clinical serviceability and durability and hence a cost-effective and accessible repair option for human welfare.

The effect of a ytterbium-doped fiber laser on titanium fused to ceramic

Aim: The aim of our study is to compare the application of fiber lasers with aluminum oxide sandblasting and CoJet, which is one of the other surface roughening methods used for the first time in this study. Investigating the effect of titanium–porcelain bond strength is another aim of this study. Methodology: In total, 96 samples of titanium discs (6 mm in diameter and 3 mm in height) were prepared in a CAD/CAM device. Samples were divided into six groups (n: 10), including the control group, according to the applied surface treatments: one-way (horizontal) scanning with a Yb fiber laser, two-way (horizontal–vertical) scanning with a Yb fiber laser, three-way (horizontal–vertical–hypotenuse) scanning with a Yb fiber laser, CoJet, sandblasting, and the control group. After using the different surface treatments on the titanium discs, SEM imaging, a wettability test, and a profilometer test were applied to the samples in each group. After the surface treatments were applied to the titanium discs, including those in the control group, low heat porcelain (VITA Titanium Porcelain), which was 4 mm in diameter and 3 mm in height, was applied according to the manufacturer's instructions. Afterwards, porcelain samples prepared with titanium inlays were placed in acrylic blocks and kept in 37°C (±1°C) distilled water for 24 hours. Shear tests were applied to the samples embedded in prepared acrylic blocks, and the results were evaluated. Results: In the statistical evaluation of the obtained data, one-way analysis of variance (one-way ANOVA) was used to compare the statistical differences of the mean values of the bond strength between titanium and porcelain. In our study, Tukey’s HSD and Dunnett’s multiple comparison statistical tests were used to determine the differences among the groups. Conclusion: According to the results of our study, the highest average bond strength values were obtained from sandblasting and three-way fiber laser roughness. As a result, no statistically significant difference was found among the groups. Although Yb fiber laser application was not found to have a statistically significant effect on titanium porcelain bond strength, this method could be useful for titanium porcelain bonding. How to cite this article: Tepe IH, Nigiz R, Seyfioglu Polat Z, Mutluay Unal S. The effect of a ytterbium-doped fiber laser on titanium fused to ceramic. Int Dent Res 2021;11(Suppl.1):128-36. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.20 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Firing process and colouring mechanism of black glaze and brown glaze porcelains from the Yuan and Ming dynasties from the Qingliang Temple kiln in Baofeng, Henan, China

Black glaze and brown glaze porcelains were an important part of ancient Chinese iron-based high temperature glazes. The excavation of black glaze and brown glaze porcelains from the Yuan and Ming dynasties at the Qingliang Temple kiln site in Baofeng, Henan, China, in 2014, enriched the firing history of this kiln site and history of Chinese ceramics. In this study, black glaze and brown glaze porcelain samples from the Qingliang Temple kiln site from the Yuan and Ming dynasties were selected and analysed via optical microscopy, laser Raman spectroscopy, focused ion beam scanning electron microscopy combined with EDS and energy dispersive X-ray fluorescence to determine their microscopic morphology, microzone composition, microstructure and chemical composition. Moreover, the main wavelength range of the brown glaze porcelain samples were measured by UV–Vis–NIR spectrophotometer systems. The main conclusions of this study are as follows. The brown glaze porcelain from the Yuan and Ming dynasties at the Qingliang Temple kiln site has two different colour layers, with the surface is brown and the bottom is black. The presence of a glass phase and α-Fe2O3 phase in the black glaze porcelain samples, and a rare ε-Fe2O3 phase in the brown glaze porcelain samples. The brown colour was a result of ε-Fe2O3 precipitation, whilst the black base layer also enhanced the brown-colouring effect. Different glaze formulations were used for brown glazed porcelain, some of which were similar to those used for black glaze porcelain and derived from the transformation of black glaze porcelain through different firing atmospheres and cooling rates. Although the formula of the brown glaze porcelain samples exhibited differences, the main wavelength difference was not large, was within the 645–682 nm range and belonged to the visible red region.

Scientific study on the celadon glaze from the Donggou kiln, China

The raw material characteristics, glaze color, mineral composition, and microstructure of green-glazed porcelain samples excavated from the Donggou kiln site in Henan Province, China were subjected to scientific investigations. The results show that the glaze formula of Donggou kiln celadon is relatively stable, and the plant ash with higher Na2O and K2O content may be used as a flux for the celadon glaze. The pan-blue celadon glaze has a wide range of dominant wavelength, concentrated and high distribution of luminosity values, low color saturation, and light degree of yellow. The high content of K2O and P2O5 is one of the main factors for the bluish glaze color. The celadon glaze of the Donggou kiln is a typical crystalline phase-separated glaze with a large number of needle-like and columnar anorthite crystals and a worm-like phase-separated structure.

Searching for the earliest use of limestone as a flux in Chinese high-fired ceramic glazes—evidence from Sr isotopic analysis of Chinese northern porcelain

Samples of northern porcelain wares dating to between the 6th and 13th centuries from the three most important northern Chinese ceramic kiln sites, Gongyi, Xing and Ding have been studied in this work. The Sr isotope and chemical compositions of the ceramic glazes of these wares have been determined. Based on the scientific results we have been able to suggest the raw materials used to make the glazes. Using Strontium isotopic analysis we have successfully shown that the earliest use of limestone as a glaze flux so far identified is during the period from the Sui to mid-Tang Dynasties (late 6th-early 9th century) to produce white slip glazed ware in the Xing kilns so it may have been ‘invented’ there.

Effect of micro/nano TiO2 addition on the densification behavior and mechanical properties of multifunctional resistant porcelains

The current study aimed at evaluating the effect of sintering temperature and TiO2 content on the density and mechanical properties of novel multifunctional resistant porcelains. In this work, a new selective mixture of available natural ceramic materials of kaolin (30 wt%), feldspar (45 wt%), and quartz (25 wt%) was used. Moreover, 3, 5, and 8 wt% TiO2 nano and microparticles were added to the mixture. The optimum sintering temperature was found to be 1150 °C, which resulted in the highest bulk density and the lowest apparent porosity of porcelain samples. The phase characterization of the prepared porcelains was carried out using the X-ray diffraction (XRD) analysis and Fourier transform infrared spectroscopy (FTIR). The XRD results of the analysis demonstrated that the samples containing 5 wt% TiO2 had the highest peak intensity of the mullite phase. In addition, the FTIR spectra confirmed the presence of crystalline mullite phase. The SEM micrographs revealed that the samples containing 5 wt% micro/nano TiO2 had the highest densification, containing the needle-like mullite phase.