Phase formation during the sintering process of a chromium ore-concentrate having a titanium-containing additive and during the firing process of the periclase-spinellide products based on it

Refractories ◽  
1993 ◽  
Vol 34 (7-8) ◽  
pp. 361-366
Author(s):  
O. V. Kvyatovskii ◽  
S. V. Kazakov ◽  
E. S. Borisovskii
Keyword(s):  
Phase Formation ◽  
Firing Process ◽  
Sintering Process ◽  
Chromium Ore

Effect of WC Addition on Phase Formation and Microstructure of TiC-Ni Composites

2008 ◽  
Vol 55-57 ◽  
pp. 353-356
Author(s):  
Nawarat Wora-uaychai ◽  
Nuchthana Poolthong ◽  
Ruangdaj Tongsri
Keyword(s):  
Liquid Phase ◽  
Tungsten Carbide ◽  
Phase Formation ◽  
Liquid Phase Sintering ◽  
Precipitation Process ◽  
Solid Solution Phase ◽  
Binder Phase ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
X Ray

In this research, titanium carbide-nickel (TiC-Ni) composites, with tungsten carbide addition, were fabricated by using a powder metallurgy technique. The TiC-Ni mixtures containing between 0-15 wt. % tungsten carbide (WC), were compacted and then sintered at 1300°C and 1400°C, respectively. The phase formation and microstructure of the WC-added TiC-Ni composites have been investigated by X-ray diffraction and scanning electron microscopy techniques. Mechanical properties of these composites were assessed by an indentation technique. The X-ray diffraction patterns showed no evidence of tungsten rich phases in the sintered WC-added cermets. This indicates that during the sintering process, tungsten carbide particles were dissolved in metallic binder phase (Ni phase) via dissolution/re-precipitation process during liquid phase sintering. The liquid phase formed during sintering process could improve sinterability of TiC-based cermets i.e., it could lower sintering temperatures. The TiC-Ni composites typically exhibited a core-rim structure. The cores consisted of undissolved TiC particles enveloped by rims of (Ti, W)C solid solution phase. Hardness of TiC-Ni composites increased with WC content. Sintering temperature also had a slight effect on hardness values.

The effect of B2O3 impurity in the original B powder on the phase formation of MgB2 during the sintering process

2011 ◽  
Vol 471 (23-24) ◽  
pp. 1660-1663 ◽  
Author(s):  
Ying Tang ◽  
Xiangjie Kong ◽  
LiDe Fang ◽  
Hongtao Wang
Keyword(s):  
Phase Formation ◽  
Sintering Process

Effect of atmosphere on the sintering process of the mixtures of caustic magnesite and chromium ore

Refractories ◽  
1987 ◽  
Vol 28 (3-4) ◽  
pp. 127-132
Author(s):  
L. B. Romanovskii ◽  
V. A. Terekhin ◽  
L. V. Krivusha ◽  
L. N. Koren
Keyword(s):  
Sintering Process ◽  
Caustic Magnesite ◽  
Chromium Ore

Synthesis and Characterization of Pb(Zr0.52Ti0.48)O3 Properties via High Planetary Mill

2017 ◽  
Vol 888 ◽  
pp. 96-102
Author(s):  
Shafiza Afzan Sharif ◽  
Julie Juliewatty Mohamed ◽  
Hasmaliza Mohamed ◽  
Zainal Arifin Ahmad ◽  
Wan Azhar Wan Yusoff
Keyword(s):  
Sintering Temperature ◽  
Xrd Analysis ◽  
High Energy ◽  
Planetary Mill ◽  
Firing Process ◽  
Material System ◽  
Sintering Process ◽  
Grain Growth Behavior ◽  
Sintering Condition

In this work, the piezoelectric material system of Pb (Zr0.52Ti0.48)O3 ceramics were synthesized by conventional solid state via high energy planetary mill reaction. This process were chosen in order to skip the calcinations and implement a single firing process which very effective to reduce the possibility of PbO loss. The effect of sintering parameters on structural behavior of pure PZT ceramic was discussed in detail. Comprehensive studies have been carried out in order get optimum parameter for sintering process, thus improved the performance of the pure PZT ceramics. Grain size properties of Pb (Zr0.52Ti0.48)O3 ceramics increased with increasing the sintering temperature and duration. However longer sintering condition (1200 °C, 3 hours) causes excessive PbO loss which leads to presence new phases in XRD analysis, promote grain growth behavior with inhomogenous microstructure and tend to have more pores.

scholarly journals Effect of MnO2 Dopant on Properties of Na+-β/β"-Al2O3 Solid Electrolyte Prepared by a Synthesizing-cum-sintering Process

2021 ◽  
Vol 27 (1) ◽  
pp. 68-76
Author(s):  
Dae-Han LEE ◽  
Jin-Sik KIM ◽  
Young-Hyuk KIM ◽  
Sung-Ki LIM
Keyword(s):  
Ionic Conductivity ◽  
Solid Electrolyte ◽  
Phase Formation ◽  
Growth Promotion ◽  
Synthesis Temperature ◽  
Negative Influence ◽  
Ion Concentration ◽  
Sintering Process ◽  
Conventional Solid State Reaction ◽  
Β Phase

In order to simplify the complexity of the conventional solid-state reaction process, Na+-β/β″-Al2O3 as a fast Na+-ionic conductive solid electrolyte was fabricated using a synthesizing-cum-sintering process combined with the double-zeta method, which is able to distribute a small amount of Li2O more homogeneously in the Na2O-Al2O3-Li2O system. Additionally, in order to enhance the ionic conductivity, MnO2 was used as a dopant to increase the Na+-ion concentration on the conduction plane in the Na+-β/β″-Al2O3 crystal structure. The relative sintered density increased with the synthesis temperature, ultimately reaching 99.7 % after synthesis at 1400 °C. The phase formation showed an overall β″-phase fraction over 90 %. The addition of MnO2 had a positive effect on the phase formation, but a negative influence on the relative density resulting from the grain growth promotion effect. The highest ionic conductivity was observed at 1.74 × 10-1 S/cm (350 °C) for the sample sintered at 1600 °C with 0.5 wt.% MnO2.

scholarly journals Latvijas minerālās izejvielas eko-keramikas izstrādei

2018 ◽  
Vol 35 ◽  
pp. 62-85
Author(s):  
Gaida Sedmale ◽  
Māris Rundāns ◽  
Mārtiņs Randers ◽  
Ingunda Šperberga ◽  
Andris Cimmers
Keyword(s):  
High Temperature ◽  
Ceramic Material ◽  
Gas Phase ◽  
Phase Formation ◽  
Raw Materials ◽  
Ceramic Materials ◽  
Firing Process ◽  
Mineral Raw Materials ◽  
Technological Processes ◽  
Insight Into

Darbā dots ieskats par iespējām izmantot Latvijas minerālās izejvielas kā bāzi vai  piedevu  keramikas  materiālu  (eko-materiālu)  izstrādei ar dažādu pielietošanas aspektu, to skaitā parādīt iespēju šo materiālu ieguves tehnoloģisko procesu optimizēšanai virzībā uz to apdedzināšanas temperatūras samazināšanu, līdz ar to reducējot kaitīgu gāzveida izmešu nonākšanu vidē. Parādīti darbu rezultāti laika periodā no 2007. g. līdz 2017. g. Tiek apskatīti un analizēti sekojoši pētījumi:neapstrādāta māla pielietošana atkritumu deponēšanas vietu noblīvēšanai;daļēji dehidratizēta māla pielietošana Cr3+, Cr6+, Zn2+ un Cu+ jonu sorbcijai, kas veidojas galvanisko procesu notekūdeņos; poru saturošas augsttemperatūras keramikas izstrāde no jauktiem izejvielu maisījumiem, kas nodrošina pietiekamu gāzveida fāzes izveidošanos keramikas apdedzināšanas procesā, veidojot poras, lai pielietotu par filtrēšanas/attīrīšanas materiālu;illīta māla piedevu izmantošana, lai pazeminātu augsttemperatūras blīvas keramikas saķepināšanas/apdedzināšanas temperatūru, iegūstot ilgspējīgu mehāniski un termiski izturīgu produktu; kā arī tehnoloģiskie procesi, kas nodrošina porainas, siltumu izolējošas keramikas materiāla ieguvi pie pazeminātām temperatūrām (ģeopolimēru metode).Mineral Raw Materials of Latvia for Development of Eco-CeramicsThe paper gives an insight into the possibilities to use Latvian mineral raw materials as a base or additives for the development of ceramic materials (eco- materials) with different application aspects, including showing the possibility of optimizing the technological processes of these materials towards the reduction of their firing temperature, thereby reducing the release of harmful gaseous effluents into the environment.The results of the works that are reported in the period were obtained from  2007 to 2017. The following studies are reviewed and analyzed: the use of untreated clay for the sealing of waste deposits; the use of partly dehydrated clay for sorption of Cr3+,6+, Zn2+ and Cu2+, which have formed in galvanic processes; the development of porous high temperature ceramics from mixes  of mineral raw materials and synthetic additives that provide a sufficient gas phase  formation in the firing process and consecutively to form pores in obtained ceramic material; the use of illite clay additives to reduce the temperature of sintering of high temperature dense mechanical and thermally durable ceramics, as well as technological processes that ensure the production of porous, heat-insulating ceramic materials at reduced temperatures (geopolymer method).

scholarly journals Impedance Spectroscopy Evolution upon Sintering of Alumina Bodies Containing Al-Rich Anodizing Sludge

2010 ◽  
Vol 636-637 ◽  
pp. 91-97
Author(s):  
M.J. Ribeiro ◽  
J.A. Labrincha
Keyword(s):  
Impedance Spectroscopy ◽  
Morphological Evolution ◽  
Thermal Analyses ◽  
Processing Parameters ◽  
Firing Process ◽  
Sintering Process ◽  
Spectroscopy Technique ◽  
Screw Extruder ◽  
Treatment Processes ◽  
Impedance Spectroscopy Technique

Al-rich sludge produced from industrial anodising and surface treatment processes had been tested in the fabrication of alumina-based materials, by using plastic extrusion as shaping technique. Long rods were produced using a vacuum screw extruder, by a careful control of all relevant processing parameters. Then, thick discs were obtained by cutting dried selected rods, to be tested as probes for sintering-dependent electrical properties. The sintering process was followed by common dilatometric/thermal analyses and results were interrelated with the evolution of electrical conductivity, estimated by impedance spectroscopy technique (IS). Results show that sintering-dependent morphological evolution up to 1300°C strongly affects the electrical behaviour of samples, and as a consequence IS seems to be a useful method to follow the firing process.

Dielectric properties of (SWCNTs)x GdBa2CuO7−δ superconductor nanocomposites

2017 ◽  
Vol 31 (31) ◽  
pp. 1750290 ◽  
Author(s):  
M. Anas ◽  
S. Ebrahim ◽  
I. G. Eldeen ◽  
R. Awad ◽  
A. I. Abou-Aly
Keyword(s):  
Dielectric Properties ◽  
Phase Formation ◽  
Dielectric Response ◽  
Single Walled Carbon Nanotubes ◽  
Superconducting Phase ◽  
Sintering Process ◽  
Superconducting Properties ◽  
Solid State Reaction Technique ◽  
Micro Cracks ◽  
Walled Carbon Nanotubes

Gd-123 superconducting phase was prepared by solid-state reaction technique. Single-walled carbon nanotubes (SWCNTs) were added in Gd-123 superconducting matrix with different concentrations during the final sintering process to obtain (SWCNTs)[Formula: see text] GdBa2Cu3O[Formula: see text] (x = 0.0–0.1 wt.%) nanoparticles–superconductor composite. The influence of SWCNTs addition on the phase formation, structural, morphological, superconducting and dielectric properties of Gd-123 phase was investigated. It was found that SWCNTs addition enhance the phase formation and does not change the crystal structure of the host Gd-123 superconducting phase. The superconducting properties of Gd-123 samples were improved after the addition of SWCNTs up to x = 0.06 wt.% due to the enhancement in intergrain connectivity by healing up of micro-cracks and reduction of defects, while these properties were retarded with further increase in x. The dielectric response of (SWCNTs)[Formula: see text] Gd-123 superconducting phase with x = 0.0, 0.01, 0.04, 0.05, 0.06 and 0.1 wt.% was measured from 100 KHz to 5 MHz at 77 K. The results reveal that for both real ([Formula: see text]) and imaginary ([Formula: see text]) parts of dielectric constant, the frequency of dispersion increased by increasing SWCNTs amount up to 0.06 wt.%, then this frequency shifted to lower values for x [Formula: see text] 0.06 wt.%. The results were discussed according to the presence and interference of both interfacial and dipolar polarizations.

Sign in / Sign up

Export Citation Format

Share Document