Influence Of Firing Temperature Research Articles

Characterisation of thick film resistor series for strain sensors

Abstract Some 10 kohm/sq. thick film resistors based on RuO 2 , ruthenates or a mixture of RuO 2 and ruthenates, were evaluated for strain gauge applications. The resistors were fired at different temperatures to estimate the influence of firing temperature on the electrical characteristics. Temperature coefficients of resistivity (TCR), noise indices and gauge factors (GF) were measured. Microstructures of the thick film resistors were analysed by SEM. The results indicate that the microstructure of thick film resistors influences the gauge factors much more significantly than the “nature” of the conductive phase.

Influence of Firing Temperature on the Microstructure and Electrical Properties of BTZ Based Dielectric Material for Ni-MLCC

Influence of Firing Temperature on the Microstructure and Electrical Properties of BTZ Based Dielectric Material for Ni-MLCC

Influence of firing temperature on correlation between thermal shock and mechanical impact resistance of refractory castables

AbstractThree refractory castables used in the aluminium industry were investigated to establish correlations, which can be applied in practice, among the relevant properties important for performance in service. To determine the influence of firing temperature on the correlations, samples were fired at 1200 and 1450°C followed by mechanical impact (at 900°C) and thermal shock tests (quenched from 950°C into water). The relevant properties were evaluated including modulus of rupture, elastic modulus, work of fracture, and thermal expansion coefficient. The results show that there is a positive correlation between thermal shock and the mechanical impact resistance as well as with the σo Rst parameter at 1200°C. Two other positive correlations were established at 1450°C, the first involving mechanical impact resistance, modulus of rupture, and σo Rst , and the second between thermal shock resistance and the R′′′′ and Rst parameters.

Sol–gel synthesis, phase relationships, and oxygen permeation properties of Sr 4Fe 6− xCo xO 13+ δ (0≤ x≤3)

Sr 4Fe 6− x Co x O 13+ δ samples have been synthesized by a sol–gel procedure for 0≤ x≤3 and the influence of firing temperature and procedure on the phase relationships has been investigated systematically. For a synthesis temperature of 1000°C, X-ray diffraction data reveal that the samples with x≤1.8 are single phase consisting of the intergrowth phase Sr 4Fe 6− x Co x O 13+ δ , while those with x>1.8 are composed of three phases – Sr 4Fe 6− x Co x O 13+ δ intergrowth phase, SrFe 1− x Co x O 3− δ perovskite phase, and Co 3− x Fe x O 4 spinel phase. Rietveld analysis of the X-ray diffraction data and thermogravimetric analysis of the samples reveal that the fraction of the perovskite phase increases as the synthesis temperature increases from 1000 to 1150°C for x>1.8. For a given synthesis/annealing temperature, the sol–gel procedure favors a higher fraction of and higher solubility of Co in the intergrowth phase compared to the conventional solid state synthesis. In the single phase samples of the intergrowth oxide Sr 4Fe 6− x Co x O 13+ δ , the oxygen permeation flux at 900°C decreases with increasing cobalt content x. On the other hand, the oxygen flux increases with increasing x in the three phase samples due to an increasing amount of the SrFe 1− x Co x O 3− δ perovskite phase.

INVESTIGATIONS OF LOW-CEMENT CASTABLES WITH SHAMOTTE AGGREGATE/MAŽACEMENČIO KAITRAI ATSPARAUS BETONO SU ŠAMOTO UŽPILDU TYRIMAI

The castables with low-cement and normal quantity cement in its composition physical and mechanical properties was investigated. Aggregates of recycled shamotte waste, which are characterised by high water absorption, were used for castables. The results of influence of firing temperature on density and cold crushing strength for three series castables were determined (Fig 1 and 2). Thermal shock resistance, bending strength and deformations of the castables were investigated additionally (Table 2 and Fig 4). The results of investigations showed the advantage of low-cement castables: better thermal shock resistance, higher cold crushing and bending strength after firing at high temperature. The properties of developed low-cement and traditional castables produced with schamotte waste aggregates were compared with the data from German, Danish and Polish castables, a special quality shamotte aggregate was used (Table 1). Low-cement castable based on shamotte waste aggregates were developed and used for producing “Ipsen” furnace lining items.

INVESTIGATIONS OF LOW-CEMENT CASTABLES WITH SHAMOTTE AGGREGATE

Summary The castables with low-cement and normal quantity cement in its composition physical and mechanical properties was investigated. Aggregates of recycled shamotte waste, which are characterised by high water absorption, were used for castables. The results of influence of firing temperature on density and cold crushing strength for three series castables were determined (Fig 1 and 2). Thermal shock resistance, bending strength and deformations of the castables were investigated additionally (Table 2 and Fig 4). The results of investigations showed the advantage of low-cement castables: better thermal shock resistance, higher cold crushing and bending strength after firing at high temperature. The properties of developed low-cement and traditional castables produced with schamotte waste aggregates were compared with the data from German, Danish and Polish castables, a special quality shamotte aggregate was used (Table 1). Low-cement castable based on shamotte waste aggregates were developed and used for producing “Ipsen” furnace lining items.

Electrochemical Characteristics of Spinel Phase LiMn2 O 4‐Based Cathode Materials Prepared by the Pechini Process: Influence of Firing Temperature and Dopants

In the past ten years, ‐based spinels have been extensively studied as positive electrode materials for lithium‐ion batteries. Our ongoing investigations have shown that the Pechini process, a low temperature synthetic method that often yields inorganic oxides of excellent phase purity and well‐controlled stoichiometry, is very effective for preparing ‐based cathode materials. It also has been shown that different firing temperatures and the selective doping of both produce materials with different electrochemical characteristics that merit further exploration.

A porcelain firing method using infrared radiation type furnace. Reference to the optimum firing temperature derived from shear bond strength and porcelain surface texture

In this study, the author, applying infra-red radiation furnace“Technomat”, investigatedthe influence of firing temperature to the property of porcelain. Three Ni-Cr alloys andtheir specified porcelain powder were examined, push shear bond test, surface roughness measurment (Rmax, Rz) and SEM analysis of porcelain surface were carried out.1. Shear bond strength was maximum under the condition 20°C lower than recommendedtemperature by 2 Beryllium-free alloys, although by Beryllium containing alloy under the specifiedtemperature (960°C) the bond strength was maximum.2. Through surface roughness measurment, those fired under 20°C lower than the specifiedtemperature showed glazed texture by every porcelain, therefore this condition is consideredclinically optimum.3. Observating surface texture by SEM analysis, the higher firing temperature becomes, themore intensely the porcelain particle's fusing undergoing.4. Shear bond strength of low Cr containing alloy showed generally weak despite decreaseof firing temperature. Increase of firing temperature for high Cr containing alloy demonstrated anincrease of bond strength value. By Beryllium-containing alloy revealed high coefficients of firingtemperature versus bond strength value.

Some properties of strontium-doped lanthanum chromite

The properties of strontium-doped lanthanum chromite (La0·84Sr0·16CrO3) are discussed, with particular attention to its application as an electrode material for MHD power generation. The influence of firing temperature on the ceramic properties and the behaviour of strontium carbonate as a sintering agent are described. The thermal conductivity is 5·1 w m−1 degk−1 between 1100 and 2000°k, and the thermal expansion 9·0×10−6 degk−1 averaged between 300 and 1100°k. Thermal shock resistance is fair and chemical stability is very good. The incorporation of strontium is found to reduce markedly the volatility in oxidizing atmospheres compared with that for pure lanthanum chromite. The electrical properties of both pure and strontium-doped lanthanum chromite are described, and for doped material a mobility deduced of 5×10−7 m2 v−1 s−1 at 300°k and 3×10−6 m2 v−1 s−1 at 1400°k. The electrical results are tentatively discussed using the formalism of Goodenough.

Influence of firing temperatures on the preparation of barium titanate.

IN the course of work on the preparation of barium titanate ceramics, it was found necessary to determine the extent of the reaction of the starting materials at various temperatures and the crystal structure of the final product.