Papers by Keyword: Sintering Temperature

Abstract: The microstructure, physical, dielectric and the piezoelectric characteristics of the (K_0.5Na_0.5) (Nb_0.9Ta_0.1) O₃ (KNNT) ceramics as a function of the sintering temperature and Nd₂O₃ dopant were inspected in this work. It was found that the sintering temperature has a significant impact on the above-mentioned properties. In the same context, the addition of HYPERLINK "https://pubchem.ncbi.nlm.nih.gov/compound/Neodymium_oxide" neodymium oxide led to remarkable improvement in the microstructure, density, dielectric and piezoelectric properties of KNNT ceramics when compared to undoped ceramics.

Abstract: Incorporation carbonate ion to hydroxyapatite (HAp) structure, known as carbonated hydroxyapatite (CHAp) is reported to reduce crystallinity, increase the solubility rate, and increase bioactivity. Sintered CHAp material is interesting because it may have a better biological response.CHAp derived from common cockle (Cerastoderma edule) shell have produced by precipitation method. This study aimed to investigate the effect of sintering temperature to compositon and crystal characteristics of CHAp. CHAp powder was sintered at 400, 600, and 800°C in air atmosphere.CHApas-preparedand sintered samples were analyzed using Energy Dispersive Spectrometry (EDS), Fourier Transform Infrared (FT-IR), and X-ray Diffractometer (XRD).EDS analysis showed that the Ca/P ratio of powder CHAp was around 1.67-1.94 (greater than the Ca/P ratioof HAp). For increasing of sintering temperature, carbonate and water content decreased, crystallinity and crystallite size increased.

Abstract: Lithium iron phospate-carbon composite (LiFePO₄/C) was successfully synthesized with various sintering temperature in order to find best synthesis condition resulting high quality of LiFePO₄/C that can be applied for environmentally friendly of cathode in lithium ion battery. It is found that the specific capacity and the stability capacity of LiFePO₄/C were improved to 17.6 mAh and 40.3% of capacity loss, respectively.

Abstract: This research is aimed to study the effect of sintering temperature on crystalline structure and surface morphology of NdFeO₃ oxide alloy materials. NdFeO₃ was synthesized by solid state reaction method with mixing of 99.9% Nd₂O₃ and 99.9% Fe₂O₃ as precursors. Three samples with different process were made in this experiment. The 1^st (#1) and 2^nd (#2) samples were sintered for 84 hours at 950°C and 600°C. Calcination procces was carried out at 950°C for 50 hours. The 3^rd (#3) sample was sintered for 84 hours at 600°C without calcination process. The samples were characterized by using SEM (Scanning Electron Microscopy) and XRD (X-Ray Diffraction). Based on the SEM characterization result, it was obtained that the sintering temperature influence on surface morphology of NdFeO₃ grain size. The XRD analyze was obtained FWHM (Full Width at Half Maximum) value of sample #1, #2 and #3 are 0.11°, 0.10°, and 0.31°, respectively. The value of FWHM was associated with the peak at 2Θ of 32.53° for all sample, it is indicated of hkl (121). Further calculation based on crystallography data was carried out by rietveld method with rietica software and the best quality will be applied as a gas sensor materials.

Abstract: Effect of sintering temperatures on phase formation, mechanical and electrical properties of lead-free Bi_0.5(Na_0.8K_0.2)_0.5Ti_0.98Zr_0.02O₃ or BNKTZ piezoelectric ceramics were investigated. The BNKTZ ceramics were prepared via a conventional solid-state sintering technique under various sintering temperature range 1100-1150°C for 2 h. The phase formation and microstructure of the ceramics were examined using X-ray diffraction (XRD) and scanning electron microscopy (SEM) method, respectively. XRD analysis indicated that all samples exhibited a single perovskite structure and no secondary phase. SEM microscopy study revealed an increase in grain size with increasing sintering temperature. The maximum values of density and maximum dielectric constant of the ceramics sintered at 1125 °C were 5.79 g/cm³ and 3446, respectively. In addition, the ceramics sintered at 1125 °C showed highest mechanical properties (HV = 4.32 GPa, HK = 5.87 GPa, E = 143 GPa and K_IC = 1.30 MPa.m^1/2). The highest values of ferroelectric and piezoelectric were found at this sintering temperature.

Abstract: This research investigated the effects of sintering temperatures on the structural, dielectric, ferroelectric, piezoelectric and mechanical properties of lead-free Bismuth Sodium Potassium Titanate (BNKT) piezoelectric ceramics. The BNKT ceramics were prepared by solid-state mixed oxide method and sintering at temperature ranging from 1100 to 1150°C for 2 h. All ceramics sample showed highly density and reach a maximum at sintering temperature 1125°C of 5.81 g/cm³. X-ray diffraction patterns exhibited pure perovskite structure with coexisting of rhombohedral-tetragonal phases for all compositions. The microstructure was characterized by Scanning Electron Microscope (SEM), from SEM image the ceramics showed cubic-like grain shape. The average grain size increased with increasing sintering temperature. The dielectric permittivity showed the optimum sintering at 1125°C with reach a maximum dielectric constant of 4,194. Furthermore, at sintering temperature 1125°C present highest strain (S_max = 0.14%) with a large normalized strain coefficient (d*₃₃ = S_max/E_max) of 233 pm/V.

Abstract: In this research, the effects of sintering temperature on phase structure, densification, microstructure, and electrical properties of modified-BNKT ceramics were investigated. Conventional sintering of lead-free 0.97Bi_0.5(Na_0.80K_0.20)_0.5TiO₃-0.03(Ba_0.70Sr_0.30)O₃ or 0.97BNKT-0.03BSrT ceramic was investigated to clarify the optimal sintering temperature for densification and electrical properties. All ceramics were prepared by a conventional mixed oxide and sintered at various temperatures from 1100 to 1150°C. XRD pattern indicated all ceramics exhibited a single perovskite without any secondary phases. The maximum density of 5.80 g/cm³ with relative density of 99.32% were observed for the ceramic sintered at 1125°C. Grain size tended to increase with increasing the sintering temperature. The good dielectric (T_d = 121 °C, T_m = 320 °C and e^¢_max = 4982) and ferroelectric properties (P_r = 16.66 µC/cm², E_c = 17.85 kV/cm and R_sq = 0.74) were obtained for the ceramic sintered at optimum sintering temperature of 1125°C.

Abstract: YAG materials have a number of unique properties, the application is very extensive, the burn is due to the temperature is too high or the residence time at high temperatures is caused. The undercurrent is the sintering temperature is too low or the holding time is not enough, resulting in product performance is too low or too small shrinkage. In this paper, the effect of sintering temperature on properties of YAG porous ceramics was investigated. The results showed that the firing temperature of the ingredients will be different and cause the same sintering process and sintering additives content of different samples burned. The increase in the content of SiO₂ in the furnish with the sintering aid tends to occur. the effect of temperature on the mechanical properties of the samples after sintering was significant, so the raw materials include 60wt%YAG, 10wt% CaO, 10wt% SiO₂ and 20wt% soluble starch, the molding process in 20MPa pressure 10min, the sintering at 1500°C for 2h, the sample porosity is 42.2%, the compressive strength is 5.8MPa, the outside shape is keep intact and the better pore microstructure is shown.

Abstract: Fabrication of Fe₂TiO₅ pellet/disk ceramics-based NTC thermistor has been performed, in order to know the effect of sintering tempertures on the electrical characteristic of 1.0 mole % MnO₂ doped-Fe₂TiO₅ ceramics. These ceramics were made by mixing commercial powders of Fe₂O₃, TiO₂ and MnO₂ with proportional composition to produce Fe₂TiO₅ based ceramic. The raw pellet was sintered at 1100 °C, 1200 °C and 1300 °C temperature for 2 hours in air. Analysis of the microstructure and crystal structure were performed by using a scanning electron microscope (SEM) and x-ray diffraction (XRD) respectively. XRD pattern showed that all of Fe₂TiO₅ ceramics made ​​at various sintering temperatures are orthorhombic The SEM images showed that the grain size of pellet ceramics increase with increasing sintering temperatures. From electrical data that was measured at temperature 30-300 °C, showed that the addition of sintering temperature decreased the thermistor constant (B), activation energy (E_a), thermistor sensitivity (α) and room temperature resistance (R_RT). Thermistor constant (B) of the ceramics was relatively big of 5778 K to 6707 K. The value of B indicated that ceramics made in this work fit the market requirement for NTC thermistor.

Abstract: This study is aimed to verify the influence of adding SiO₂ and CaO in the sintering temperature of hexaferrite, obtained by standard ceramic methods. The powders were weighed in stoichiometric amounts, milled for 1 hour under a high energy mill and calcined at 1000 °C/24h. To study the effect of concentration of additives on the microstructure of the hexaferrite samples were prepared without additives, and with simultaneous addition of SiO₂ and CaO, wherein the total concentration of the additive was 1%. The morphology and particle size of the samples were determined by SEM and the crystal structure was determined by XRD and the phases were quantified by the Rietveld method. The XRD data showed the predominance of magnetoplumblico structure with hexagonal symmetry and space group P63/mmc. All samples have distributed grain heterogeneously, clustered in different masses, with acute forms and some of them featuring hexagonal shapes with different sizes.