scholarly journals Effect of TiO2 on the Sintering Behavior of Low-Grade Vanadiferous Titanomagnetite Ore

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4376
Author(s):  
Songtao Yang ◽  
Weidong Tang ◽  
Xiangxin Xue
Keyword(s):  
Perovskite Phase ◽  
Calcium Ferrite ◽  
Sintering Behavior ◽  
Low Grade ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
Degradation Index ◽  
Tio2 Content ◽  
Iron Ore Fines

Low-grade vanadiferous titanomagnetite ore (LVTM) is as an important mineral resource for sintering ore manufacturing. Furthermore, TiO2 has a significant effect on the sintering process of iron ore fines. The effects of TiO2 on the metallurgical properties, microstructure, and mineral composition of LVTM sinter were investigated by sintering pot tests, X-ray diffraction (XRD), scanning electron microscopy (SEM), and mineral phase microanalysis. The results were as follows: as the TiO2 content increased from 1.75% to 4.55%, the flame front speed and productivity decreased, while the reduction degradation index (RDI) and softening properties deteriorated. In addition, the tumbler index (TI) values reached a maximum at TiO2 = 1.75%. In addition, with increasing TiO2 content, an increase in the magnetite and perovskite phase, and a decrease in calcium ferrite and hematite were found with an increase in TiO2 content. Thus, the lower the TiO2 content, the better the quality of the sinter.

scholarly journals The Mechanism of the Effect of Al2O3 Content on the Liquid Phase Fluidity of Iron Ore Fines

Processes ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 931 ◽  
Author(s):  
Heping Li ◽  
Shengli Wu ◽  
Zhibin Hong ◽  
Weili Zhang ◽  
Heng Zhou ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Mineral Composition ◽  
Phase Formation ◽  
Iron Ore ◽  
Al2o3 Content ◽  
Calcium Ferrite ◽  
Sintering Process ◽  
Liquidity Index ◽  
Iron Ore Fines

The sintering process is significantly important for the ironmaking in China because of the large amount of sinter consumed. Al2O3 is an important element determining the quality and quantity of sinter. However, different conclusions have been made regarding the effects of Al2O3 on the amount and fluidity of the liquid phase formed in the sinter phase. Therefore, it is necessary to examine the effects of Al2O3 content on the amount and fluidity of the liquid phase. The present work investigated the effects of different Al2O3 contents of iron ore fines on the liquid phase formation, mineral composition, and consolidation strength. The results showed that a small amount of Al2O3 increased the amount of calcium ferrite, making the liquid phase formation easier. As the Al2O3 content in iron ore fines increased, the liquidity index decreased continuously, while the fluidity and the consolidation strength of the sintered body were directly related to the content squared. The quality of the sinter is optimal when the Al2O3 content of the iron ore fines is about 2 wt % (the SiO2 content is 4 wt %).

scholarly journals Sintering Behavior and Technological Properties of Low-Temperature Porcelain Tiles Prepared Using a Lithium Ore and Silica Crucible Waste

Minerals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 731 ◽  
Author(s):  
Lihua Peng ◽  
Shan Qin
Keyword(s):  
Low Temperature ◽  
Ceramic Body ◽  
Raw Material ◽  
Quantitative Phase Analysis ◽  
Sintering Behavior ◽  
Low Grade ◽  
Technological Properties ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
Porcelain Tiles

Porcelain tiles are a building material that has been widely used in recent years and that consumes substantial resources during the sintering process. This study reports on the production of low-temperature porcelain tiles by using low-grade lithium ore (LO) and silica crucible waste (SCW) in a new SiO2–Al2O3–Na2O–K2O–Li2O system. The firing temperature of the porcelain tiles was reduced from 1260 °C to 1070 °C by adding 30% LO instead of feldspar in a modified triaxial ceramic body, and SCW was recycled and used as a raw material. These actions help to reduce the carbon emissions produced during sintering and achieve sustainable development. The effect of phase transitions on the sintering and technological properties of the porcelain tiles was studied by quantitative phase analysis, using X-ray diffraction (XRD). Secondary mullite (0–19%) can be formed at 1040–1100 °C, where more quartz and cristobalite will be retained, which increases the rupture modulus of the porcelain tiles. While the vitreous phase increases rapidly at 1100–1160 °C, the closed pores (0.1–33.1%) will simultaneously expand, causing a decrease in compactness. The results show that low-grade LO (with a cost similar to that of feldspar) allows for the production of porcelain tiles with better process performance at lower temperatures (≤1100 °C).

Sintering Pot Test on Improving TiO2-Containing Ore’s Allocated Proportion

2011 ◽  
Vol 311-313 ◽  
pp. 850-853 ◽  
Author(s):  
Zhen Kui Yin ◽  
Jing She Li ◽  
Shu Feng Yang
Keyword(s):  
Compressive Strength ◽  
Blast Furnace ◽  
Calcium Ferrite ◽  
Sintering Process ◽  
Tio2 Content ◽  
Mineral Structure

The effects of different TiO2-containing ore’s allocated proportion on quality, mineral structure and sintering process of Xuan steel sinter were studied in this paper. The results showed that the increasing of the TiO2-containing ore’s allocated proportion was disadvantageous to the sinter sample’s anti-compressive strength, and the yield and tumbler strength of sinter were decreased although the velocity of sintering was improved. The tumbler strength decreased from 68.67% to 63.33%, and the main reason is that the content of perovskite increases and the content of calcium ferrite decreases with the increasing of TiO2-content in the sinter. The TiO2-content in the sinter should be controlled less than 1.3% considering effect of TiO2-content on sintering process, burdening and iron making of blast furnace in all.

A Study on Nanometer-Sized BaTiO3-Based Dielectric for Ni-MLCC with Y5V Specification

2005 ◽  
Vol 475-479 ◽  
pp. 1129-1132
Author(s):  
Zhen Ji ◽  
Zhigang Xiao ◽  
Sen Wang ◽  
You Song Gu ◽  
Cheng Zhou ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Dielectric Material ◽  
Dissipation Factor ◽  
Dielectric Medium ◽  
Sintering Behavior ◽  
Manufacturing Cost ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
Chemical Route ◽  
Transmission Electron

In order to meet the demand on the miniaturization and manufacturing cost reduction of the multilayer ceramic capacitors we have developed a nano-BaTiO3-based non-reducible dielectric material through a soft chemical route. The particle size has been decreased down to the level of 30nm and the dielectric medium could be co-fired with Ni-electrodes under a N2+H2 reducing atmosphere. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and volume shrinkage have been employed to detect the sintering behavior and microstructure evolution including grain growth, pore formation and body densification. Dielectric measurements showed, after a sintering process at 1200°C for 2h, the dielectric constant was 8800, the dissipation factor was less than 2%, the insulation resistance was about 12~13exp Ω.cm, and the temperature coefficients of capacitance were less than 22% and -82% at -30°C and 85°C respectively. On the basis of the results it is anticipated that the material could be used for the Ni-MLCC with thin dielectric layers with a Y5V specification in the Electron Industries Association standard.

Composition, Structure and Properties of PZT-BT Ceramics Prepared by Two-Stage Sintering

2009 ◽  
Vol 421-422 ◽  
pp. 436-439 ◽  
Author(s):  
Wanwilai C. Vittayakorn ◽  
Rattikorn Yimnirun ◽  
Supon Ananta
Keyword(s):  
Perovskite Phase ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
Two Stage ◽  
Fine Grain ◽  
Pure Perovskite Phase ◽  
One Step ◽  
Composition Structure ◽  
The One ◽  
System 1

Ceramic solid solutions within the system (1-x)PZT-xBT, where x = 0.1, 0.2, 0.3, 0.4 and 0.5, were prepared by conventional mixed-oxide method combined with a two-stage sintering procedure. A sintering time of 2 h at 1000 °C followed by a second step in the temperature range of 1000-1200 °C for 2 h was employed to all samples and compared to the one-step sintering process. Phase formation, densification and microstructure of all ceramics were examined via X-ray diffraction (XRD), Archimedes method and scanning electron microscope (SEM). The results lead to the conclusion that the pure perovskite phase and high densification of (1-x)PZT-xBT ceramics with fine grain can be successfully achieved under suitable two-stage sintering conditions.

scholarly journals Phase Development in the Sintering of a Hematite–Ilmenite Ore Blend

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 800
Author(s):  
Edson K. Chiwandika ◽  
Seong-Kyu Cho ◽  
Sung-Mo Jung
Keyword(s):  
Glass Phase ◽  
Sintering Behavior ◽  
Low Grade ◽  
Iron Ores ◽  
X Ray Diffraction ◽  
X Ray ◽  
Phase Development ◽  
Sinter Bonding ◽  
Hematite Ore ◽  
Increasing Temperature

The use of low-grade iron ores has attracted a lot of interest where fines from these ores are sintered to improve their strength. Ti-containing ores are one of the abundantly available iron ores of low-grade. The sintering of the hematite–ilmenite ore blends has several challenges, which include the formation of perovskite. The sintering behavior of a hematite–ilmenite ore sinter blend was investigated in 75 vol% N2, 24 vol% CO2, and 1 vol% CO in the temperature range of 1373 to 1523 K. Phase development and distribution of metallic elements were investigated by x-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), and electron probe microanalysis (EPMA). The addition of ilmenite ore to hematite ore increased the temperature of melt formation. More titanium (Ti) was distributed in the glass phase with increasing temperature. Morphological change showed that the amount of sinter-bonding phase generated was low, below 1473 K. Weak sinter bonding strength might be caused by the presence of Ti in the glass phase at high temperature. This might affect the fracture toughness of the glass phase.

Gasketing optimized for large sample volume in the diamond anvil cell: first application to MgGeO3and implications for structural systematics of the perovskite to post-perovskite transition

2008 ◽  
Vol 41 (1) ◽  
pp. 38-43 ◽  
Author(s):  
C. David Martin ◽  
Yue Meng ◽  
Vitali Prakapenka ◽  
John B. Parise
Keyword(s):  
Perovskite Structure ◽  
Diamond Anvil Cell ◽  
Perovskite Phase ◽  
Volume Ratio ◽  
Sample Volume ◽  
X Ray Diffraction ◽  
A Value ◽  
Large Sample Volume ◽  
Diamond Anvil

Structure models of MgGeO3post-perovskite (Cmcm) are presented, along with a structure survey, demonstrating that all perovskite, post-perovskite and CaIrO3-type structures (ABX3) have specific ranges of the volume ratio between cation-centered polyhedra (VA:VB). The quality of the reported diffraction data and MgGeO3structure models is enhancedviaimplementation of a new graphite gasket for the diamond anvil cell, which stabilizes a larger sample volume, improving powder statistics during X-ray diffraction, andviathe thermal insulation required to achieve ultra-high temperatures while laser-heating samples at pressures near 100 GPa. The structure survey supports the theory that the pressure–temperature conditions under which the perovskite/post-perovskite phase transition occurs can be estimated by extrapolating the change inVA:VBto a value of 4, which corresponds to a maximum tilt ofBX6octahedra in the perovskite structure (Pbnm) where inter-octahedral anion–anion distances match the average intra-octahedral anion–anion distance. Once these short inter-octahedral distances between anions are reached in the perovskite structure, further tilting of octahedra and decrease of theVA:VBratio does not occur, driving the transition to post-perovskite structure as pressure is increased.

Increasing Competency Of SD Teachers In Thematic Learning Planning Through Group Supervision Using Collaborative Approaches In SDN Tlambah 2 Karangpenang Sampang

2019 ◽  
Vol 4 (2) ◽  
pp. 44-54
Author(s):  
Namin Namin
Keyword(s):  
Action Research ◽  
Action Observation ◽  
Group Supervision ◽  
Low Grade ◽  
Classroom Teachers ◽  
Collaborative Approach ◽  
Research Subjects ◽  
Thematic Learning ◽  
Planning Action

Abstrak: Penelitian ini dilakukan dengan tujuan meningkatkan kompetensi guru di SDN Tlambah 2, Kabupaten Karangpenang Sampang. Perencanaan pembelajaran tematik dalam meningkatkan kualitas pembelajaran tematik. Subjek penelitian dalam penelitian tindakan kelas ini adalah guru kelas di Sekolah Dasar Negeri Tlambah 2, Kabupaten Karangpenang Sampang. Penelitian tindakan kelas ini dilaksanakan dalam dua siklus, menggunakan tahapan perencanaan, tindakan, observasi dan refleksi dalam setiap siklus. Data yang terkumpul dianalisis secara kuantitatif dan kualitatif. Dari penelitian tindakan kelas ini disimpulkan bahwa supervisi kelompok dengan pendekatan kolaboratif dapat meningkatkan kompetensi guru kelas di SDN Tlambah 2 Kabupaten Karangpenang Sampang.   Kata kunci: kolaboratif, kompetensi, tematik     Abstract: This research was conducted with the aim of increasing the competency of teachers in SDN Tlambah 2, Karangpenang Sampang District, Spreading thematic learning planning in improving the quality of thematic learning. Research subjects in this action research are low grade teachers in Tlambah 2 Public Elementary School, Karangpenang Sampang District. School action research means it is carried out in two cycles, using the stages of planning, action, observation and reflection in each cycle. The collected data is analyzed quantitatively and qualitatively. From this school action research concludes that group supervision with a collaborative approach can improve the competence of classroom teachers in SDN Tlambah 2, Karangpenang Sampang District.   Keywords: collaborative, competence, thematic

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