Synthesis and Thermal Characterization of Dysprosium Zirconate

2014 ◽  
Vol 223 ◽  
pp. 54-61 ◽  
Author(s):  
Marta Mikuśkiewicz ◽  
Michał Stopyra ◽  
Grzegorz Moskal

Results of investigations related to synthesis and thermal properties analysis of the Dy2Zr2O7phase was presented in this article. This material was obtained during high temperature synthesis in an actual pressure of 15 MPa, in vacuum of 3×10-6MPa, and at 1350°C with 2 hours of exposure. Feedstock materials were submicrocrystalline powders of dysprosia Dy2O3and zirconia ZrO2. Both powders were mechanically blended in alcohol before the sintering process. The final product was analysed from the phase’s composition point of view. It was revealed that main constituent elements were dysprosium zirconate with an overall formula of Dy2Zr2O7and others were Dy zirconates with a non-stoichiometric character. The presence of zirconia was found with tetragonal types of unite cell. This fact evidences that partial dissolution of Dy2O3in ZrO2took place. The obtained material was characterized by calorimetric investigations in the thermal range from 25 to 1450°C.

Author(s):  
Gunter Heymann ◽  
Elisabeth Selb ◽  
Toni Buttlar ◽  
Oliver Janka ◽  
Martina Tribus ◽  
...  

By high-pressure/high-temperature multianvil synthesis a new high-pressure (HP) phase of Co3TeO6 was obtained. The compound crystallizes in the acentric trigonal crystal system of the Ni3TeO6-type structure with space group R3...


2019 ◽  
Vol 16 ◽  
pp. 95-101
Author(s):  
Jelena Maletaškić ◽  
Jelena Luković ◽  
Katsumi Yoshida ◽  
Toyohiko Yano ◽  
Ryosuke S.S. Maki ◽  
...  

2012 ◽  
Vol 602-604 ◽  
pp. 148-152
Author(s):  
Lek Sikong ◽  
Wasin Triprakong

Silver nano-particles (AgNPs) films were prepared and coated on glass fibers by reduction of [Ag(NH3)2]+ complex with sucrose at temperature of 400-600°C. The effect of AgNO3 solution used as a source of silver was also investigated. The synthesized films were characterized by scanning electron microscopy (SEM), X-ray diffractometer (XRD) and electron dispersive X-ray spectrometer (EDX). It was found that both concentration and temperature have an effect on crystal growth, morphology and hydrophobic property of silver nanoparticles on surfaces of glass fibers. High temperature synthesis can partially cause grain coarsening of AgNPs on the films. The hydrophobic property of these silver coarsened grains was found to increase at the calcined temperature of 600°C, leading to easily removed from the surface coating.


2005 ◽  
Vol 475-479 ◽  
pp. 1627-1630 ◽  
Author(s):  
Rui Zhu Zhang ◽  
Zhi Meng Guo ◽  
Cheng Chang Jia ◽  
Guangfeng Lu

This paper researched the fabrication of perovskite synrock by self-propagating high temperature synthesis (SHS) and the characterization of the products. This synthesis process is simpler, the fabricated synrock can immobilize waste loading up to 35wt% SrO with satisfied physical properties (density>4.2g•cm-3, open porosity<0.2%, Leach rate<1.0 g•m-2•d-1). The structure analyses by XRD and SEM/EDS show that the major phase is perovskite which well agrees with the design. It proves that SHS offer a suitable Sr-waste synroc which is favorable for geological disposal.


2020 ◽  
Vol 59 (6) ◽  
pp. 3579-3584
Author(s):  
Sun Woo Kim ◽  
Xiaoyan Tan ◽  
Corey E. Frank ◽  
Zheng Deng ◽  
Huaiyu Wang ◽  
...  

1986 ◽  
Vol 1 (2) ◽  
pp. 275-279 ◽  
Author(s):  
Osamu Yamada ◽  
Yoshinari Miyamoto ◽  
Mitsue Koizumi

Self-propagating high-temperature synthesis (SHS), also called combustion synthesis, is useful for fabricating numerous ceramics. In the case of SiC, heat released from the exothermic reaction is not sufficient to completely convert the mixed reactants of constituent elements into SiC in the usual nonadiabatic experimental system. This disadvantage could be overcome by a new ignition process called, the “direct passing method of electric current.” By using this method, stoichiometric fine SiC powder could be obtained rapidly and efficiently with low electric power. This paper also involves the effect of particle size of Si and C initial reactant powders on conversion efficiency into SiC and also on particle size of SiC powder fabricated by this method.


2007 ◽  
Vol 546-549 ◽  
pp. 2179-2182 ◽  
Author(s):  
Ling Bai ◽  
Xing Yu Zhao ◽  
Chang Chun Ge

Sintering of the Self-Propagating High-Temperature Synthesis (SHS) of β-Si3N4 powder with 6.67 wt.% Y2O3 and 3.33 wt.% Al2O3 as sintering additives has been emphatically investigated using hot-press sintering process. The relative density of hot-pressed β-Si3N4 reached near to the full densification (99.43%) at 1700°C. The similar micrographs with self-reinforcing rod-like β-Si3N4 grains forming an interlocking structure were observed. The better mechanical properties of hot-pressed Si3N4, such as the hardness (16.73GPa), fracture toughness (5.72 MPa·m1/2) and bending strength (611.72MPa) values, were obtained at 1700°C. The results indicate that good sinter ability can be obtained with the cheaply SHS of silicon nitride powder for preparing silicon nitride materials, which will make the cost of silicon nitride materials lowered.


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