Bitumen and bituminous binders. Accelerated long-term ageing/conditioning by the rotating cylinder method (RCAT)

2007 ◽  
Keyword(s):  
Rotating Cylinder ◽  
Bituminous Binders ◽  
Cylinder Method

Viscosity Evaluation of Multi-phases Flux by Rotating Cylinder Method

2009 ◽  
Vol 95 (12) ◽  
pp. 807-812 ◽  
Author(s):  
Sohei Sukenaga ◽  
Shinichiro Haruki ◽  
Yoshinori Yamaoka ◽  
Noritaka Saito ◽  
Kunihiko Nakashima
Keyword(s):  
Rotating Cylinder ◽  
Cylinder Method

Effects of basicity and CaF2 on the viscosity of CaF2–CaO–SiO2 slag for electroslag remelting process

2019 ◽  
Vol 116 (6) ◽  
pp. 638 ◽  
Author(s):  
Yigui Lao ◽  
Yunming Gao ◽  
Fangjie Deng ◽  
Qiang Wang ◽  
Guangqiang Li
Keyword(s):  
Rotating Cylinder ◽  
Electroslag Remelting ◽  
Experimental Conditions ◽  
Ft Ir ◽  
Cylinder Method ◽  
The Fourier Transform ◽  
The Relationship ◽  
Complex Anions ◽  
Silicate Complex ◽  
Ft Ir Spectroscopy

Effects of the basicity and the CaF2 content on viscosity of CaF2–CaO–SiO2 slag with high CaF2 content for electroslag remelting process were investigated by the rotating cylinder method in the temperature ranging from 1773 to 1533 K. The relationship between the structure and the viscosity variation of the slag was also clarified by the Fourier transform infrared (FT-IR) spectroscopy of water-quenched slags. The results show that the viscosity gradually decreases with the increase in the basicity of the slag from 1 to 3 under the present experimental conditions. It is found that the CaO does not depolymerize all silicate complex anions for the slag with the basicity of 1 at 1773 K and there are still some bridging oxygens. With the increase in the basicity to 3, the silicate complex anions are almost completely depolymerized to simple ions. As the CaF2 content increases from 40 to 80 mass%, the viscosity of the slag decreases due to the dilution of CaF2 for the concentration of the silicate complex anions in unit volume of the slag. Moreover, the effect of the temperature on the viscosity is not remarkable. The activation energy of viscous flow exhibits the decrease from 40.4 to 26.7 kJ · mol−1 with the increase in the basicity from 1 to 3, and also the decrease from 66.6 to 31.0 kJ · mol−1 with the increase in the CaF2 content from 40 to 80 mass%.

Effect of Dense Layer Formation on Dissolution Rate of MgO-C Refractory in Molten Slag

2006 ◽  
Vol 45 ◽  
pp. 162-166 ◽  
Author(s):  
Hiroyuki Sunayama ◽  
Masayasu Kawahara
Keyword(s):  
Chemical Composition ◽  
Corrosion Rate ◽  
Corrosion Test ◽  
Molten Slag ◽  
Cylindrical Specimen ◽  
Rotating Cylinder ◽  
Dense Layer ◽  
Layer Formation ◽  
The Matrix ◽  
Cylinder Method

The corrosion test for magnesia-carbon refractory, MgO-C, with dense layer has been carried out by a rotating cylinder method at 1673 K. The specimen, which was a cylinder of 25 mm diameter and 25mm height, was rotated in molten slag at 50 rpm. The chemical composition of slag was CaO-SiO2-FeO-MgO-CaF2. The corrosion rate was determined by the variation of radius of the cylindrical specimen against corrosion time. The decrease of radius was obtained by a calculation of dissolved MgO into the slag. In addition, the diameter of the specimen was measured with a slide calipers after the corrosion test. The cylindrical specimen was heated to form a dense layer before the corrosion test. The corrosion rate of the MgO-C refractory with dense layer was slower than that of the MgO-C refractory without dense layer. The oxidized layer, where the dense layer formed, dissolved at much the same rate as the MgO brick. The dense layer probably obstructed contact between slag and carbon in the matrix, and then oxidation of C by slag did not take place. Formation of the dense layer was effective to inhibit corrosion of MgO-C refractory by molten slag.

Research on the Viscosity of CaF2-SiO2-Al2O3-CaO-MgO Slag System by the Thermodynamic Software

2013 ◽  
Vol 634-638 ◽  
pp. 42-46
Author(s):  
Yuan She ◽  
Jian Tao Ju ◽  
Zhi Yuan Jiao ◽  
Zhao Hui Zhang
Keyword(s):  
Physical Properties ◽  
Systematic Study ◽  
Mass Fraction ◽  
Slag System ◽  
Graphite Crucible ◽  
Rotating Cylinder ◽  
Slag Viscosity ◽  
Measuring Apparatus ◽  
Refining Slag ◽  
Cylinder Method

In order to find out a method of computation on the viscosity of CaF2-SiO2-Al2O3-CaO-MgO slag system, which is accurate, rapid and convenient, a systematic study has been carried out. The refining slag samples have been made by the method of rotation-regression-orthogonal combination design during the test. When the temperature of the flux of the samples were 1600°C~1400°C, the experiment was performed by internal rotating cylinder method involving a spindle with the RTW-10 flux physical properties measuring apparatus in graphite crucible per 50°C, meanwhile, the viscosity of slag system were estimated by thermodynamic software FactSage per 50°C. Then, according to the viscosity results of calculation at 1600°C, the viscosity calculation equation was established, which was the relation of the mass fraction of every components and the value of the slag viscosity. Furthermore, the interaction of two components on the influence of the viscosity of slag was discussed.

Influence of Nb2O5 and basicity on the viscosity and structure of CaO-SiO2-Nb2O5-CeO2-CaF2 slag system

2020 ◽  
Vol 117 (3) ◽  
pp. 307
Author(s):  
Zhuang Ma ◽  
Zengwu Zhao ◽  
Wentao Guo ◽  
Zhi Wang
Keyword(s):  
Activation Energy ◽  
Slag System ◽  
Rotating Cylinder ◽  
Degree Of Polymerization ◽  
X Ray Diffraction ◽  
Structural Units ◽  
X Ray ◽  
Reducing Atmosphere ◽  
Bayan Obo ◽  
Cylinder Method

In order to utilize niobium concentrate of Bayan Obo effectively, the effect of Nb2O5 and basicity on the viscosity of CaO-SiO2-Nb2O5-5.0 wt.% CeO2-5.0 wt.% CaF2 slag system was studied from 1653 to 1813 K in reducing atmosphere by rotating cylinder method. For the same condition, the as-quenched samples were investigated through X-ray diffraction and Raman spectroscopy. The results show that the viscosity, break temperature and activation energy of viscous flow decrease with the increase of Nb2O5 and basicity. Raman spectra show that the Nb4+ ions exist in the form of [NbO6] octahedron with different distortion and little [NbO4] tetrahedron in the slags. The Nb2O5 addition and basicity lower the degree of polymerization, where the complex Si-O network is depolymerized into simple structural units.

scholarly journals Effects of BaO and B2O3 on the Absorption of Ti Inclusions for High Titanium Steel

Metals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 165
Author(s):  
Boyang Li ◽  
Xin Geng ◽  
Zhouhua Jiang ◽  
Yu Hou ◽  
Wei Gong
Keyword(s):  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Titanium Oxide ◽  
Mold Flux ◽  
Rotating Cylinder ◽  
Experimental Results ◽  
Transfer Coefficients ◽  
Mold Fluxes ◽  
Cylinder Method

In order to study the effect of BaO or B2O3 on the absorption of Ti inclusions, the effects of mold fluxes with different contents of BaO (0~15%) or B2O3 (0~15%) on the mass transfer coefficients of TiO2 or TiN were studied with the rotating cylinder method. The experimental results show that with the addition of BaO in the mold flux, the mass transfer coefficient of TiO2 increases from 4.58 × 10−4 m/s to 6.08 × 10−4 m/s, that of TiN increases from 3.09 × 10−4 m/s to 4.41 × 10−4 m/s, 2CaO·MgO·2SiO2 is transformed into BaO·2CaO·MgO·2SiO2, and the Ti inclusions combine with CaO to form CaTiO3. With the addition of B2O3 in the mold flux, the mass transfer coefficient of TiO2 increases from 4.58 × 10−4 m/s to 7.46 × 10−4 m/s, that of TiN increases from 3.09 × 10−4 m/s to 5.50 × 10−4 m/s, CaO and B2O3 combine to 2CaO·B2O3, and Ti inclusions exist in the form of TiO2. During the experiment, TiN will be transformed into titanium oxide.

scholarly journals Viscosity estimation model of fluorine-containing mold flux for continuous casting

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0247828
Author(s):  
Zhongyu Zhao ◽  
Junxue Zhao ◽  
Boqiao Qu ◽  
Yaru Cui
Keyword(s):  
Continuous Casting ◽  
Mass Fraction ◽  
Mold Flux ◽  
Rotating Cylinder ◽  
Spectrometric Analysis ◽  
Nonlinear Regression Analysis ◽  
Estimation Model ◽  
X Ray ◽  
Low Viscosity ◽  
Cylinder Method

A viscosity estimation model for fluorine-containing mold flux for continuous casting was investigated based on the Arrhenius formula and the rotating cylinder method combined with nonlinear regression analysis. This model is highly applicable and not limited by the slag of a certain composition. For most slag compositions, the viscosities estimated with this model deviated from the measured values by no more than 10%, which was in better agreement with the measured values than the viscosities estimated by the Riboud, Iida and Mills models. According to the model calculation and experimental detection, a viscosity isogram of CaF2-Na2O-Al2O3-CaO-SiO2-MgO slag was produced, and the mass fraction of CaF2 in the low-viscosity zone was nearly 14%. An X-ray fluorescence spectrometric analysis of slag after the viscosity test showed that CaF2 and Na2O were significantly reduced, and the measured viscosity was greater than the theoretical viscosity due to the volatilization.

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