Influence of Higher Waste Loading on Crystallization of Titanosilicate Glass-Ceramics

AbstractSphene (CaTiSio5 ) is obtained as the main crystalline phase in Na2O-A12O3-CaO-TiO2-SiO2 glass-ceramics containing up to ∼ 15 wt% of simulated nuclear fuel recycle waste, by maintaining the precursor glass at ∼ 1050°C for sufficient time to allow nucleation and crystal growth. The implications for production of an engineering-scale waste form are discussed.

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Preparation of glass-ceramics with diopside as the main crystalline phase from low and medium titanium-bearing blast furnace slag

Ceramics International ◽

10.1016/j.ceramint.2017.09.019 ◽

2018 ◽

Vol 44 (2) ◽

pp. 1384-1393 ◽

Cited By ~ 22

Author(s):

Dongfeng He ◽

Chong Gao ◽

Jiangtao Pan ◽

Anjun Xu

Keyword(s):

Blast Furnace ◽

Crystalline Phase ◽

Blast Furnace Slag ◽

Glass Ceramics ◽

Main Crystalline Phase ◽

Furnace Slag

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Synergistic Effect of K2O and Al2O3 on the Crystallization and Structure of Na2O-CaO-SiO2-MgO-Al2O3-ZnO of Glass-Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.655.234 ◽

2015 ◽

Vol 655 ◽

pp. 234-239

Author(s):

Jian Wei Cao ◽

Zhi Wang

Keyword(s):

Grain Size ◽

Synergistic Effect ◽

Crystalline Phase ◽

Crystallization Temperature ◽

Crystallization Behavior ◽

Raw Materials ◽

Glass Ceramics ◽

Melt Quenching ◽

Main Crystalline Phase

The Na2O-CaO-SiO2-MgO-Al2O3-ZnO glass-ceramics was prepared from the phosphorus slag as main primary raw materials by melt quenching technique. The effects of K2O and Al2O3 on crystallization behavior and structure of glass-ceramics were investigated by DSC, XRD and SEM. It is shown that the main crystalline phase is combeite (Na4Ca4(Si6O18)) in glass-ceramics. K2O and Al2O3 do not change the main crystalline phase of glass-ceramics, but K2O increases the crystallization temperature, Al2O3 increases the crystallization temperature, obviously decreases the grain size. The K2O isometric replaces Na2O at the same time the Al2O3 isometric to replace SiO2, reduced the grain size.

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The Crystallization Behaviors of SiO2-Al2O3-CaO-MgO-TiO2 Glass-Ceramic Systems

Crystals ◽

10.3390/cryst10090794 ◽

2020 ◽

Vol 10 (9) ◽

pp. 794

Author(s):

Feifei Lai ◽

Mei Leng ◽

Jiangling Li ◽

Qingcai Liu

Keyword(s):

Mechanical Properties ◽

Glass Ceramic ◽

Crystalline Phase ◽

Three Dimensional ◽

Glass Ceramics ◽

Exothermic Peak ◽

Obvious Effect ◽

Prepared Glass ◽

Main Crystalline Phase ◽

Hardness Values

To evaluate the crystallization behavior of Ti-bearing blast furnace slag-based glass ceramics, SiO2-Al2O3-CaO-MgO-TiO2 systems with various TiO2 were investigated. The crystallization process and mechanical properties were analyzed. The results show that with TiO2 increasing, exothermic peak temperature (Tp) decreases, and the crystallization is promoted by the introduction of TiO2. A small amount of TiO2 (≤4%) addition can significantly promote crystallization, and when TiO2 continues to increase, the crystallization is decreased slightly. The Avrami parameter (n) of all samples is less than 4, indicating that in prepared glass-ceramics, it is hard to achieve three-dimensional crystal growth. The main crystalline phase is akermanite–gehlenite. The addition of TiO2 has no obvious effect on the type of main crystalline phase. The prepared glass-ceramic with 4% TiO2 show good mechanical properties with the hardness values of 542.67 MPa. The recommended content of TiO2 is 4% for preparing glass-ceramics.

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Effect of B2O3 and P2O5 Addition on the Phase Separation and Crystallization of Li2O-MgO-Al2O3-SiO2 Glass-Ceramics

Materials Science Forum ◽

10.4028/www.scientific.net/msf.848.243 ◽

2016 ◽

Vol 848 ◽

pp. 243-248 ◽

Cited By ~ 2

Author(s):

Zhen Hong Bao ◽

Li Feng Miao ◽

Wei Hui Jiang ◽

Jian Min Liu ◽

Jian Liang ◽

...

Keyword(s):

Thermal Expansion ◽

Phase Separation ◽

Thermal Expansion Coefficient ◽

Expansion Coefficient ◽

Crystalline Phase ◽

Raw Materials ◽

Glass Ceramics ◽

Lithium Silicate ◽

Solid State Method ◽

Main Crystalline Phase

B2O3- or P2O5-doped Li2O-MgO-Al2O3-SiO2 (LMAS) glass-ceramics were prepared by solid state method using Li2CO3, MgO, Al2O3 and SiO2 as the raw materials, B2O3 or P2O5 as the additives. The effects of adding B2O3 and P2O5 on the phase separation, crystallization and thermal expansion coefficient were investigated by means of X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron microscopy (SEM) and thermal dilatometer, respectively. The results showed that B2O3 or P2O5 addition could promoted phase separation of glass and increased the size of spherical phase separation droplet. With the addition of B2O3 or P2O5, the crystallization temperatures (Tc) of LMAS system decreased from 764 oC to 726 oC and 764 oC to 750 oC, respectively. However, the crystalline phase compositions did not changed, and β-quartz solid solution (s.s) (Li2Al2Si3O10) was still the main crystalline phase, and lithium silicate (Li2SiO3) and forsterite (Mg2SiO4) were the minor phases. The thermal expansion coefficient (α) of B2O3-doped and P2O5-doped LMAS glass-ceramics in the temperature range 20-600 oC were 5.215×10-6/ oC and 5.008×10-6/ oC, respectively, which were higher than that of LMAS glass-ceramics (α=3.790×10-6/ oC).

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Crystallization Kinetics and Microhardness of MgO–Al2O3–SiO2 Glass Ceramics with Low Melting Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1023.39 ◽

2014 ◽

Vol 1023 ◽

pp. 39-42

Author(s):

Qiang Lu ◽

Shu Jiang Liu

Keyword(s):

Melting Temperature ◽

Crystalline Phase ◽

Annealing Temperature ◽

Glass Ceramics ◽

Calorimetric Study ◽

Strong Impact ◽

Phase Sequence ◽

Main Crystalline Phase ◽

High Quartz ◽

Glass Compositions

The authors report a deferential scanning calorimetric study of MgO–Al2O3–SiO2glasses which possess low melting temperature due to introduction of some quantity of B2O3, Li2O and CaF2. It is shown that the content of Li2O has a strong impact on the overlapping extent of the rates of nucleation and crystal growth. High-quartz tends to precipitate at low temperature (~1173 K) for the studied glasses, irrespective of Li2O content. With increasing annealing temperature, spodumene and cordierite form as main crystalline phase for the samples with high and low Li2O content, respectively, and then cristobalite crystals occur for both glass compositions. Microhardness firstly increases and then decreases, depending on crystalline phase sequence, and a maximum microhardness value is obtained to be 10.5 GPa.

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Optimization of heat treatment of glass-ceramics made from blast furnace slag

High Temperature Materials and Processes ◽

10.1515/htmp-2020-0059 ◽

2020 ◽

Vol 39 (1) ◽

pp. 539-544

Author(s):

Yi-Ci Wang ◽

Pei-Jun Liu ◽

Guo-Ping Luo ◽

Zhe Liu ◽

Peng-Fei Cao

Keyword(s):

Heat Treatment ◽

Blast Furnace ◽

Blast Furnace Slag ◽

Orthogonal Experiment ◽

Glass Ceramics ◽

Iron And Steel ◽

Heat Treatment Regime ◽

Main Crystalline Phase ◽

Optimum Heat ◽

Furnace Slag

AbstractCaO–MgO–Al2O3–SiO2 glass-ceramics with diopside as the main crystalline phase were prepared by melting blast furnace slag obtained from Baotou Iron and Steel Company. The effect of heat treatment on the crystallization behavior of glass-ceramics, containing a large proportion of melted blast furnace slag, was studied by means of differential thermal analysis and scanning electron microscopy. The optimum heat-treatment regime was obtained by orthogonal experimental results for glass-ceramics in which blast furnace slag comprised 70% of the composition and 1% Cr2O3 and 4% TiO2 were used as nucleating agents. The nucleation temperature was 750°C for 2.5 h and the crystallization temperature was 930°C for 1 h. Under this regime, the performance of the glass-ceramic was better than that of other groups in the orthogonal experiment.

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Preparation of Glass-Ceramics Using Molybdenum Tailings

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.284-286.1431 ◽

2011 ◽

Vol 284-286 ◽

pp. 1431-1434 ◽

Cited By ~ 1

Author(s):

Jin Rui Zhang ◽

Ru Wang

Keyword(s):

Heat Treatment ◽

Thermal Analysis ◽

Differential Thermal Analysis ◽

Crystalline Phase ◽

Glass Ceramics ◽

Chemical Properties ◽

The Other ◽

Raw Material ◽

Physical Chemical ◽

Nucleation Agents

In order to utilization the molybdenum tailings which be deposited in large quantities. Test used it to prepare glass-ceramics as main raw material, TiO2 as nucleation agents and CaO-Al2O3-SiO2 system and wollastonite as the principal crystalline phase. Heat treatment system of glass-ceramics was based on the differential thermal analysis. The crystalline phase, microstructure and characteristics of glass-ceramics were analysis by XRD, SEM and physical, chemical properties test. The result shows that the performance of glass-ceramics was superior to the other types of building decoration stone.

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Crystallization Behavior and Performance of MgO-Al2O3-SiO2 Glass-Ceramics by Sintering

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.92.65 ◽

2010 ◽

Vol 92 ◽

pp. 65-71 ◽

Cited By ~ 4

Author(s):

Pei Xin Zhang ◽

Li Gao ◽

Qiu Hua Yuan ◽

Hai Lin Peng ◽

Xiang Zhong Ren ◽

...

Keyword(s):

Thermal Expansion ◽

Flexural Strength ◽

Thermal Expansion Coefficient ◽

Expansion Coefficient ◽

Crystallization Process ◽

Glass Ceramics ◽

X Ray Diffraction ◽

Low Thermal Expansion ◽

Main Crystalline Phase ◽

And Performance

The glass-ceramics of MgO-Al2O3-SiO2 system were prepared by sintering technology. The crystallization process of MgO-Al2O3-SiO2 glass-ceramics was investigated with X-ray diffraction (XRD), scanning electron microscopy (SEM), and other techniques; the discussion of breaking strength, thermal expansion coefficient and relevant properties at different sintering temperatures was also presented. The results show that: (1) The main crystalline phase isα-cordierite at different sintering temperatures, and the samples show high flexural strength and low thermal expansion coefficient; (2) with the increase of sintering temperature, the content of crystal phase increases, while the thermal expansion coefficient decreases evidently, the flexural strength and tightness density rise up first, then go down.

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