scholarly journals Crystallization Kinetics of Modified Basalt Glass

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 5043
Author(s):  
Yonglin Huo ◽  
Guilu Qin ◽  
Jichuan Huo ◽  
Xingquan Zhang ◽  
Baogang Guo ◽  
...  
Keyword(s):  
Crystallization Kinetics ◽  
Basalt Fiber ◽  
Raw Material ◽  
Scanning Calorimetry ◽  
Crystalline Phases ◽  
Basalt Glass ◽  
Stable Production ◽  
Heat Treated ◽  
Quenching Method ◽  
Kinetics Of

As the raw material for the production of basalt continuous fibers in Sichuan, basalt glass (BG) and modified basalt glass (MBG) were prepared by the melt quenching method with the basalt and chemically modified basalt, respectively. The crystallization kinetics of BG and MBG were investigated by differential scanning calorimetry (DSC) according to Kissinger methods. The results revealed that it is difficult for both glasses to crystallize at a high temperature. In addition, the crystallization activation energy of MBG is much higher than that of BG, which indicates that MBG is more difficult to crystallize than BG. The crystalline phases seemed to be formed from the surface of the two glasses. The morphologies and crystal structure of the crystalline phases in the heat-treated BG and MBG were analyzed by scanning electron microscope (SEM/EDX) and XRD. It was found that only a small amount of crystalline phase can be observed in the MBG, which indicates that the crystallization ability of the MBG was greatly suppressed. Results of this initial investigation indicate that chemical modification can effectively suppress the crystallization tendency of basalt glass and improve its thermal stability, which opens up an effective way for the industrial scale and stable production of basalt fiber.

Crystallization Kinetics of β-Spodumene/Cordierite-Based Glass-Ceramics

2016 ◽  
Vol 881 ◽  
pp. 83-88 ◽  
Author(s):  
Rafael Bianchini Nuernberg ◽  
Oscar Rubem Klegues Montedo
Keyword(s):  
Crystallization Kinetics ◽  
Glass Ceramics ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Kinetics Parameters ◽  
Crystalline Phases ◽  
Cordierite Glass ◽  
Thermal And Electrical Properties ◽  
Kinetics Of

This work aims to investigate the crystallization kinetics of β-spodumene/cordierite glass-ceramics. Thus, three glasses with compositions based predominantly on cordierite (C), β-spodumene (L) and in a molar ratio 1:1 of both phases (CL) were prepared. The kinetics parameters such as activation energy for crystallization (ranging from 160 to 358 kJ/mol) and Avrami exponent (ranging from 1.4 to 10.7) were determined by means of non-isothermal methods using differential scanning calorimetry (DSC). Additionally, the samples were crystalized according to DSC analyses and characterized by using x-ray diffraction (XRD). The main detected crystalline phases were β-spodumene to the glass L, cordierite to the glass C and β-quartz, mulite and spinel to the glass CL. Considering the thermal and electrical properties of these crystalline phases, these glass-ceramics have potential use for LTCC (Low Thermal Co-fired Ceramics) applications.

Crystallization Kinetics of Iron Rich Glass-Ceramic Obtained from Waste of Steel Industry

2014 ◽  
Vol 775-776 ◽  
pp. 244-249 ◽  
Author(s):  
André Luís Luza ◽  
Débora Cristina Niero Fabris ◽  
Edivelton Soratto Gislon ◽  
Morgana de Medeiros Machado ◽  
Oscar Rubem Klegues Montedo
Keyword(s):  
Crystallization Kinetics ◽  
Glass Ceramic ◽  
Absorption Spectrometry ◽  
Differential Analysis ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray ◽  
Heat Treated ◽  
Wet Ground ◽  
Kinetics Of

The main objective of this work was to study the crystallization kinetics of glass-ceramic obtained from steel waste. Two compositions were melted at about 1350 °C. The obtained frits were dried and re-melted. Each composition was then wet ground, dried, and chemically characterized (X-ray fluorescence and atomic absorption spectrometry), structurally (X-ray diffraction), and thermally (thermal differential analysis). Then the powders were compacted and the samples were dried and heat treated in a kiln between 690 and 890 °C. After, the crystallized bodies were ground and the crystalline phases were identified by X-ray diffraction. Results showed that the main formed crystalline phases were magnetite, hematite, Fe2.95Si0.05O4, and CaAl2Fe4O10. The activation energies obtained by the Kissinger method were between 348 and 423 kJ.mol-1, whereas the Avrami parameter was obtained between 0.76 and 1.1 indicating surface crystallization.

scholarly journals Thermal Properties and Non-Isothermal Crystallization Kinetics of Poly (δ-Valerolactone) and Poly (δ-Valerolactone)/Titanium Dioxide Nanocomposites

Crystals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 452 ◽  
Author(s):  
Waseem Saeed ◽  
Abdel-Basit Al-Odayni ◽  
Abdulaziz Alghamdi ◽  
Ali Alrahlah ◽  
Taieb Aouak
Keyword(s):  
Titanium Dioxide ◽  
Crystallization Kinetics ◽  
Isothermal Crystallization ◽  
Three Dimensional ◽  
Degree Of Crystallinity ◽  
Simultaneous Occurrence ◽  
Scanning Calorimetry ◽  
Isothermal Crystallization Kinetics ◽  
The Stability ◽  
Kinetics Of

New poly (δ-valerolactone)/titanium dioxide (PDVL/TiO2) nanocomposites with different TiO2 nanoparticle loadings were prepared by the solvent-casting method and characterized by Fourier transform infra-red, differential scanning calorimetry, X-ray diffraction and scanning electron microscopy, and thermogravimetry analyses. The results obtained reveal good dispersion of TiO2 nanoparticles in the polymer matrix and non-formation of new crystalline structures indicating the stability of the crystallinity of TiO2 in the composite. A significant increase in the degree of crystallinity was observed with increasing TiO2 content. The non-isothermal crystallization kinetics of the PDVL/TiO2 system indicate that the crystallization process involves the simultaneous occurrence of two- and three-dimensional spherulitic growths. The thermal degradation analysis of this nanocomposite reveals a significant improvement in the thermal stability with increasing TiO2 loading.

scholarly journals Non-Isothermal Crystallization Kinetics of Injection Grade PHBV and PHBV/Carbon Nanotubes Nanocomposites Using Isoconversional Method

2020 ◽  
Vol 4 (2) ◽  
pp. 52
Author(s):  
Thaís Larissa do Amaral Montanheiro ◽  
Beatriz Rossi Canuto de Menezes ◽  
Larissa Stieven Montagna ◽  
Cesar Augusto Gonçalves Beatrice ◽  
Juliano Marini ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Crystallization Kinetics ◽  
Isothermal Crystallization ◽  
Model Fitting ◽  
Polarized Light ◽  
Isoconversional Method ◽  
Degree Of Crystallinity ◽  
Gamma Aminobutyric Acid ◽  
Scanning Calorimetry ◽  
Kinetics Of

Carbon nanotubes (CNT)-reinforced polymeric composites are being studied as promising materials due to their enhanced properties. However, understanding the behavior of polymers during non-isothermal crystallization is important once the degree of crystallinity and crystallization processes are affected when nanoparticles are added to matrices. Usually, crystallization kinetics studies are performed using a model-fitting method, though the isoconversional method allows to obtain the kinetics parameter without assuming a crystallization model. Therefore, in this work, CNTs were oxidized (CNT-Ox) and functionalized with gamma-aminobutyric acid (GABA) (CNT-GB) and incorporated into a poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) matrix. The influence of the addition and functionalization of CNT in the crystallization kinetics of PHBV was evaluated using the isoconversional method with differential scanning calorimetry (DSC), and by polarized light optical microscopy (PLOM) and Shore D hardness. The incorporation and functionalization of CNT into PHBV matrix did not change the Šesták and Berggren crystallization model; however, the lowest activation energy was obtained for the composite produced with CNT-GB, suggesting a better dispersion into the PHBV matrix. PLOM and Shore D hardness confirmed the results obtained in the kinetics study, showing the smallest crystallite size for CNT-containing nanocomposites and the highest hardness value for the composite produced with CNT-GB.

Glass Forming Ability and Crystallization Kinetics of Al-Mg-Ni-La Metallic Glasses

2014 ◽  
Vol 960-961 ◽  
pp. 161-164 ◽  
Author(s):  
Juan Mu ◽  
Hai Feng Zhang
Keyword(s):  
Crystallization Kinetics ◽  
Glass Forming Ability ◽  
Continuous Heating ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Glass Forming ◽  
Dsc Measurements ◽  
Mg Addition ◽  
Kinetics Of ◽  
Thermal Stability Of

Glass forming ability and crystallization kinetics of Al-Mg-Ni-La alloys have been investigated by X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The maximum thickness achievable in glasses of Al76Mg11Ni8La5and Al69Mg18Ni8La5ribbons were 200 and 120 μm, respectively. The crystallization temperature and peak temperature indicated by DSC measurements displayed dependence on the heating rate during continuous heating, and were coincident with Lanoka’s relationship. The activation energies for the crystallization reactionExwere obtained from the Kissinger’s equation. The results show the Mg addition is beneficial to the thermal stability of the amorphous phase.

Preparation and Crystallization Kinetics of FeSiB Amorphous Ribbons under Non-Isothermal Regime

2014 ◽  
Vol 605 ◽  
pp. 35-38
Author(s):  
Eirini Varouti
Keyword(s):  
Thermal Stability ◽  
Differential Scanning Calorimetry ◽  
Chemical Composition ◽  
Crystallization Kinetics ◽  
Structural Changes ◽  
Scanning Calorimetry ◽  
Amorphous Ribbons ◽  
Isothermal Regime ◽  
Kinetics Of

The aim of the present work was the preparation and characterization of FeSiB amorphous magnetic ribbons with the following chemical composition: Fe80SixB20-x, x=5,6,8 and Fe75Si15B10. Differential Scanning Calorimetry was employed in order to study the thermal stability and structural changes during the transformations that took place. Much emphasis is placed on the analysis of the crystallization kinetics.

scholarly journals Phase transformations during continuous heating: effect of Sn addition on the microstructure of Ti-13Mo alloy

2020 ◽  
Vol 321 ◽  
pp. 05017
Author(s):  
M.G. de Mello ◽  
F.H. da Costa ◽  
R. Caram
Keyword(s):  
Lattice Parameter ◽  
Continuous Heating ◽  
Phase Precipitation ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
Β Phase ◽  
Ω Phase ◽  
Α Phase ◽  
Heat Treated ◽  
Kinetics Of

The addition of Sn to the Ti-Mo system can diminish the formation of ω phase and slow down the precipitation kinetics of α phase due to the low atomic diffusivity of Sn atoms in Ti. To explore α phase precipitation in Ti-13Mo and Ti-13Mo-6Sn (wt.%) alloys, differential scanning calorimetry (DSC) was applied using different heating rates to determine ω phase dissolution, α phase precipitation and β transus temperatures. The DSC results were then used to determine the aging heat treatment temperatures. Samples were heat-treated at 600 °C for 1 h and 24 h to examine microstructure features. The addition of Sn to Ti-13Mo alloy was found to increase the β phase lattice parameter, increasing β transus temperatures and resulting in microstructures with heterogeneous and coarser α phase precipitation.

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