The samples used in this study are created from a porcelain mixture. This mixture is high strength aluminous which electrotechnical engineering (high voltage insulators). contains clay, kaolin, feldspar, alumina, and small amount of other admixtures. made with three different compression pressures (80, 90, 110 MPa). Impulse excitation technique, termodilatometry, termogravimetry to determine Young's modulus. analyses performed the temperature range 30 °C 1100 heating rate 5 °C/min static air...

The production technology of ceramic materials has a significant impact on the physical properties final products. This paper shows differences in density and Young's modulus samples made by five different compression pressures. Due to increasing pressure, particles are closer each other therefore porosity material decreases, increases. influence firing temperature compacting pressure electroporcelain is studied after up 1200 °C with heating rate 5 °C/min for cooling stage. from mixture....

The influence of the compression pressure on thermal expansion, bulk density, and porosity electroporcelain type C 130 made under pressures 70 MPa, 90 110 MPa is studied after firing up to 1400 °C by a step 100 °C. mass loss shrinkage samples decreases with pressure. density differs very little extent. At temperature °C, lowest obtained for sample pressed highest 1300 which common production, at MPa.

A non-isothermal kinetics of the two-step dehydroxylation illite is carried out using thermogravimetric analysis. The experiments are performed on powder samples with heating rates from 1 °C min–1 to 10 in a dynamic atmosphere dry air. From these measurements, values apparent activation energy calculated by Kissinger method. Ea for first and second step (195 ± 16) kJ mol−1 (354 25) mol–1, respectively. results also show that trans-vacant layer controlled one-dimensional diffusion an...

Abstract A dynamic thermomechanical analysis (D-TMA) apparatus is described for measuring the resonant frequency of flexural vibration and internal damping sample using impulse excitation technique (IET). Since measurement conducted at temperatures up to 1250 °C, an electromagnetic impulser used excitation. The free vibrations are registered by electret microphone, stored then converted into a spectrum fast Fourier transform, from which can be found. furnace built refractory porous alumina...

The two-step dehydroxylation of illite is studied using the differential scanning calorimetry on powder samples with heating rates from 1 to 10 °C min−1 in a dynamic argon atmosphere. values apparent activation energy and pre-exponential factor are calculated Kissinger method. determined for trans-vacant layer (227 ± 6) kJ mol−1 (2.87 0.09)×1013 min−1, respectively. results also show that this process can be characterized by 1D diffusion-controlled reaction instantaneous nucleation rate. For...

Abstract Dependence of the AC conductivity C-130 type electroporcelain on compaction pressure was measured. The samples were manufactured from spray-dried mixtures using isostatic in vacuum at 5 different pressures (70 MPa to 110 MPa, 10 step size). measurements performed 25 frequencies ranging 50 Hz 3 MHz room temperature with dimensions × mm . In addition pressure, effect firing temperatures studied (1100°C and 1200°C). highest values observed case raw samples, due an amount physically...

Abstract The aim of the paper is reveal effect quartz particle size on mechanical properties electroporcelain subjected to cyclic test. This describes influence electroporcelain. amount was controlled during sample preparation. Eight groups samples were manufactured by extrusion with addition 0, 1, 2, and 4 wt.% two different grain sizes 200 μm 64 μm. Samples fired at temperature 1320 °C, which a common for this type ceramics. Once nominal value strength each group determined, cyclically...

Abstract Specimens composed of 50 wt.% kaolin, 25 quartz, and feldspar were subjected to constant tensile stress during linear heating at 5 °C/min rate measure their deformation behavior. Deformation occurs temperatures above 300 °C depends on the stress: higher external stresses led a more pronounced expansion sample dehydroxylation region. Consequently, 1100 °C, sintering samples in liquid state intense contraction occurred. The dilatation behaviour was governed by combined effect opposing...

This paper describes the influence of quartz on mechanical properties electroporcelain. The amount was controlled during sample preparation. Four groups samples were made by extrusion with addition 0 wt.%, 1 2 and 4 wt.% quartz. Samples fired at a temperature 1320 °C, which is common for this type ceramics. After finding nominal value strength each group, cyclically tested 50% strength. Tested cracked three-point bending machine obtaining Due to results, it can be concluded that residual...

The paper presents the influence of compression pressure on apparent activation energy crystallization Al-Si spinel phase. This is achieved samples which are made from elecroporcelain mixture under pressures 70 MPa up to 110 MPa. determined series non-isothermal thermodilatometry experiments using Kissinger method. results show that decreases with pressure. values MPa, 80 90 100 and (670 ± 24) kJ mol−1, (568 40) (543 12) mol–1, (526 30) (506 16) respectively. decrease may be caused by...

The pore size distribution of porcelain samples is studied using thermoporometry. Thermoporometry a calorimetric method where the structure described from melting or freezing point depression liquid confined in pores. derived differential scanning calorimetry during process ice As probe, water used. thermal analysis performed temperature interval –20 °C to 5 with heating rate 0.1 °C/min. results are compared mercury intrusion porosimetry. It found that distributions depend on equations which...

Pressed ceramics have a great usage in wide variety of applications, especially when the emphasis is on strength material. The mechanical can be already influenced during production process, for example by rheological properties, technology formation ceramic body, moisture content raw mixture, as well firing temperature. High voltage insulators are an integral part electrical infrastructure worldwide and they made with pressing. For this reason, it very important to optimize from economical...