Investigations on phase constitution, mechanical properties and hydration kinetics of aluminous cements containing magnesium aluminate spinel

2013 ◽  
Vol 39 (7) ◽  
pp. 8393-8400 ◽  
Author(s):  
Jin-hong Li ◽  
Bi-ya Cai ◽  
Wu-wei Feng ◽  
Yu-qin Liu ◽  
Hong-wen Ma
Keyword(s):  
Mechanical Properties ◽  
Magnesium Aluminate ◽  
Magnesium Aluminate Spinel ◽  
Hydration Kinetics ◽  
Phase Constitution ◽  
Kinetics Of

Hydration Kinetics of Aluminate Cement Containing Magnesium Aluminate Spinel

2011 ◽  
Vol 295-297 ◽  
pp. 945-948
Author(s):  
Bi Ya Cai ◽  
Jin Hong Li ◽  
Hong Wen Ma ◽  
Xiao Qian Jiang
Keyword(s):  
Diffusion Process ◽  
Hydration Heat ◽  
Magnesium Aluminate ◽  
Magnesium Aluminate Spinel ◽  
Hydration Kinetics ◽  
Hydration Rate ◽  
Kinetics Of ◽  
And Diffusion ◽  
Aluminate Cement ◽  
Reaction And Diffusion

The hydration heat of aluminate cement containing magnesium aluminate spinel (MA-spinel) and Commercial Lafarge cement are studied. The results show that five stages exist in the hydration processes of both cements, e.g. pre-induction, induction, acceleration, deceleration and stabilization stage. TheNvalues of the two cements are both lower than 1 in acceleration stage, on the contary higher than 1 in stabilization stage. As a result, the hydration is mainly controlled by nucleation reaction and diffusion process in acceleration stage and stabilization stage respectively. The hydration heat of aluminate cement containing MA-spinel is lower than Lafarge cement. Accordingly, the hydration rate of aluminate cement containing MA-spinel is slower than that of Lafarge cement.

Irradiated Microstructures of Magnesium Aluminate Spinel and their Controlling Factors

1998 ◽  
Vol 540 ◽  
Author(s):  
C. Kinoshita ◽  
S. Matsumura ◽  
K. Yasuda ◽  
T. Soeda ◽  
M. Noujima
Keyword(s):  
Mechanical Properties ◽  
Radiation Resistance ◽  
Recent Progress ◽  
Controlling Factors ◽  
Magnesium Aluminate ◽  
Magnesium Aluminate Spinel ◽  
Void Swelling ◽  
Characteristic Features ◽  
Related Characteristic ◽  
Alpha Alumina

AbstractThis paper reviews our recent progress in study on the strong resistance of magnesium aluminate spinel to void swelling during irradiation, along with the related characteristic features of its radiation damage. Comparative experimental results on irradiated microstructures and mechanical properties in magnesium aluminate spinel and alpha-alumina are shown in terms of controlling factors of radiation resistance of the former crystal. It is experimentally shown that structural vacancies due to non-stoichiometry provide effective recombination sites for displaced cations to suppress the formation of interstitial loops. Decreased formation of interstitial loops enhances the further recombination of interstitials and vacancies and thereby the formation of voids.

Effect of TiO2 on Mechanical Properties and Microstructure of Magnesium Aluminate Spinel Refractories

2011 ◽  
Vol 284-286 ◽  
pp. 638-641
Author(s):  
Jun Cong Wei ◽  
Xiao Cui Han ◽  
Chun Hui Gao ◽  
Jian Kun Huang ◽  
Jun Bo Tu
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Titanium Dioxide ◽  
Phase Composition ◽  
High Temperature ◽  
Physical Properties ◽  
Room Temperature ◽  
Magnesium Aluminate ◽  
Magnesium Aluminate Spinel

MgO-Al2O3-TiO2 composite refractories were prepared by using magnesium aluminate spinel (MgAl2O4) and titanium dioxide as main starting materials and being sintered at high temperature. The influences of titanium dioxide additions on the room temperature physical properties, phase composition and microstructure were investigated. The phase composition and microstructure were tested by means of XRD and SEM. The results revealed that with increasing TiO2 content, the densification of the composites first increased sand then decreased and maximized at 4% TiO2 loading. This showed appropriate amount of TiO2 could contribute to the sintering of the composites due to the solid solution of TiO2 in magnesium aluminate spinel.

Phase Composition, Microstructure and Mechanical Properties of Aluminous Cements Containing Magnesium Aluminate Spinel

2011 ◽  
Vol 492 ◽  
pp. 467-471
Author(s):  
Jin Hong Li ◽  
Ling Xin Tong ◽  
Wen Cai Zhou
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Phase Composition ◽  
Magnesium Aluminate ◽  
Magnesium Aluminate Spinel ◽  
Curing Time ◽  
Sintering Process ◽  
Microstructure And Mechanical Properties ◽  
New Type ◽  
Aluminous Cement

A new type aluminous cement containing magnesium aluminate (MA) spinel was prepared from mixtures of limestone, magnesian and bauxite at different ratios by sintering process. The phase composition, microstructure and mechanical properties of aluminous cements containing magnesium aluminate spinel were investigated in this paper. According to the XRD results, the magnesium aluminate spinel (MA),calcium monoaluminate (CA) and calcium bialuminate (CA2) are the primary phases of the obtained aluminous cements with a small quantity of calcium silicoaluminate (C2AS) and remained alumina (Al2O3). The results of SEM indicate that the MA mainly exist in the shape of octahedron with the length of about 2-5 μm, and it is agglomerated with the tabular or flaky-shaped CA among the obtained aluminous cements. In addition, the compressive strength of castables containing obtained aluminous cements increase obviously with the content of CA rising or the curing time increasing.

Sign in / Sign up

Export Citation Format

Share Document