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Mechanical and microstructural response of densified silica glass under uniaxial compression: Atomistic simulations

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Chinese Physics B 2020年第10期29卷 507-514页

作者： Yi-Fan Xie Feng Feng Ying-Jun Li Zhi-Qiang Hu Jian-Li Shao Yong Mei School of Science China University of Mining and TechnologyBeijing 100083China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyBeijing 100083China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Institute of Defense Engineering AMSPLABeijing 100036China

We investigate the mechanical and microstructural changes of the densified silica glass under uniaxial loading-unloading via atomistic simulations with a modified BKS potential. The stress–strain relationship is found to include three respective stages: elastic, plastic and hardening regions. The bulk modulus increases with the initial densification and will undergo a rapid increase after complete densification. The yield pressure varies from 5 to 12 GPa for different densified samples. In addition, the Si–O–Si bond angle reduces during elastic deformation under compression, and 5-fold Si will increase linearly in the plastic deformation. In the hardening region, the peak splitting and the new peak are both found on the Si–Si and O–O pair radial distribution functions, where the 6-fold Si is increased. Instead, the lateral displacement of the atoms always varies linearly with strain, without evident periodic characteristic. As is expected, the samples are permanently densified after release from the plastic region, and the maximum density of recovered samples is about 2.64 g/cm^3, which contains 15 % 5-fold Si, and the Si–O–Si bond angle is less than the ordinary silica glass. All these findings are of great significance for understanding the deformation process of densified silica glass.

关键词： silica glass uniaxial compression densification atomistic simulation

Structure Characterization of F-doped silica glass

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Journal of Wuhan University of Technology(Materials Science) 2009年第1期24卷 137-139页

作者：谢峻林邓涛 Key Laboratory for silicate Materials Science and Engineering of Ministry of Education Wuhan University of Technology

Pure and fluorine-doped silica glass were fabricated by plasma chemical vapour deposition （PCVD） and characterized using Raman and infrared spectrum. The change in Raman intensity of 945 cm-1 peak, relating to ≡Si-F stretching vibration, agrees with the change of F content. Compared with measured wavenumber in IR spectrum, the calculated absorption wavelength confirms the incorporation form of F into the glass, the detail of which is a tetrahedron with a Si atom in the center coupled with one F atom and three network O atoms. Such structure identification may be useful for explaining some properties of F-doping silica glass.

关键词： silica glass fluorine PCVD incorporation form

Influence of Annealing on the Structure of silica glass

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Journal of Wuhan University of Technology(Materials Science) 2013年第5期28卷 902-906页

作者：苏英 YIN Hong HE Xingyang 周永恒 Laboratory of Nanophotonic Functional Materials and Devices South China Normal University School of Civil Engineering and Architecture Hubei University of Technology

Two types of high-purity synthetic silica glasses were annealed with different processes in precision annealing furnace. The thermal stress and structure of samples were analyzed by two types of stress instruments and Fourier transform infrared spectrometer. After being annealed at1 070 ℃ for 6 days and then cooled slowly, optical path difference （OPD） caused by stress in the center and edge of Type III silica glass with a diameter of 150 mm and thickness of 50 mm decreased from 6 to 2 nm/cm. Meanwhile, with the same annealing process, fictive temperature of small-size Type III glass decreased to 939 ℃, and structural stability of silica glass was improved. In addition, after being annealed at 1 100 ℃ for 5 hours and then cooled slowly, internal stress in Type IV silica glass with a thickness of 1 mm was basically eliminated, and its fietive temperature decreased from 1 421 to 966 ℃.

关键词： silica glass annealing thermal stress fictive temperature

OH Diffusion in silica glass Preform During Jacketing Process by Oxy-Hydrogen Burner

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光学学报 2003年第S1期23卷 76-77页

作者： B.H.Kim S.R.Han U. C.Paek W.-T.Han S. K.Oh Department of Information and Communications Kwangju Institute of Science and Technology (K-JIST) I Oryong-dong Buk-gu Gwangju 500-712 South Korea Engineering and R & D group Optical Communication Product Division Information & Communication Business Samsung Electronics Co. LTD. # 94-1 Imsoo-dongGumiGyeong-Buk 730-350 South Korea

Radial distribution of OH diffusion in silica glass preform during jacketing process using a oxy-hydrogen burner was investigated by FTIR spectroscopy. The OH peaks at the jacketing boundary and the surface of the pre... 详细信息

关键词： FTIR spectroscopy silica glass

Synthesis and optical properties of europium pentafluoropropionate 1,10-phenanthroline complex and its silica glass

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Frontiers of Optoelectronics 2011年第4期4卷 382-386页

作者： Jiangbo SHE Dongdong LI State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision MechanicsChinese Academy of Sciences (CAS) Department of Electronic and Information Engineering Xi'an Institute of Post & Telecommunications

Europiumpentafluoropropionate 1,10-phenanthroline complex, Eu（C2F5COO）3·Phen（Phen =1,10-phenanthroline）, were synthesized and characterized by elemental analysis, Fourier transform infrared spectroscopy（FT-IR）, photoluminescence（PL） spectroscopy and thermogravimetric analysis（TA）. At the same time, its silica glass was synthesized by in situ processes. The excitation spectra of the complex demonstrate that the energy collected by “antenna ligands” was transferred to Eu3+ions efficiently. The room-temperature PL spectra of the complexes are composed of the typical Eu3+ions red emission, due to transitions between5D0→7FJ（J = 0 → 4）.The decomposition temperature of the complex was 290°C, which indicates the host complex is quite stable to heat. Then the affection of anneal temperatures on PL properties of SiO2glass were studied. The PL intensity of the SiO2glass annealed at 160°C was higher than other annealed temperatures for 24 h in air.

关键词： organometallic complex silica glass luminescent property

KINETIC FACTORS AFFECTING THE CORROSION OF SiO_2 IN silicaTE glassES CAUSED BY ALKALINE SOLUTIONS

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Journal of Wuhan University of Technology(Materials Science) 1995年第2期10卷 1-10页

作者：吴正明步恒祉 Wuhan Univ of Technology China

The corrosion of a ZrO2 containing alkali re-sistant silicate glass, float glass and silica glass caused by the aqueous solution of NaOH was studied by use of correlation method with spectrophotometry. Effects of the corroding tem-perature, time and solution concentration on the rate of reac-tion and the degree of corrosion were investigated; effects of the apparent activation energy and the experimental value of frequency factor on the rate constant were discussed.

关键词： alkali-resistant glass silica glass float glass kinetics of alkaline corrosion

Infrared broadband emission of Bismuth-Thulium co-doped Lanthanum-Aluminum-silica glasses

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Infrared broadband emission of Bismuth-Thulium co-doped Lant...

Sol-Gel Processing of silica Nuclear Waste glasses

战略性新兴产业的培育和发展——首届云南省科协学术年会

作者： Tran Minh Hau 陈明厚 School of Material Science and Engineering Kunming University of Science and Technology

The Bi-Tm co-doped SiO-AlO-LaO(SAL) glasses,which exhibited a broadband near-infrared emission was investigated by the optical absorption and photoluminescence *** super broadband near-infrared emission from 1000 to 2100 nm,covering the whole O,E,S,C,and L bands,was observed in the Bi-Tm co-doped samples,as a result of the overlap of the Bi-related emission band(centered at 1270 nm) and the emission from Tm H→F transition(1440 nm) as well as Tm F→H transition(1800 nm).Relative luminescence intensity at 1270,1440 and 1800 nm wavelength varies depending on the mixing ratio of Bi and Tm,and the full width at half-maximum(FWHM) extending from 1000 to 1600 could be 400 *** results indicated that Bi-Tm co-doped SiO-AlO-LaO glasses could provide potential applications in tunable lasers as well as the broadband optical amplifiers in WDM system.

关键词： silica glass Energy transfer Bi-Tm co-doped Luminescence Broadband

来源： cnki会议评论

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New Journal of glass and Ceramics 2011年第3期1卷 105-111页

作者： Andrzej Deptula Magdalena Milkowska Wieslawa Lada Tadeusz Olczak Danuta Wawszczak Tomasz Smolinski Fabio Zaza Marcin Brykala Andrzej G.Chmielewski Kenneth C.Goretta Institute of Nuclear Chemistry and Technology(INCT) WarsawPoland Italian National Agency for New Technologies Energy and Environment(ENEA)CR CasacciaRomeItaly Asian Office of Aerospace Research and Development Japan

A complex Sol-Gel process has been used for synthesis of silica glasses designed to contain high-level nuclear wastes. Cs, Sr, Co, and Nd (generically denoted Me) were used, the last as surrogate for actinides. Gels in the form of powders and sintered compacts were prepared by hydrolysis and polycondensation of tetraethoxide/Me nitrate solutions, which contained ascorbic acid as a catalyst. Thermal treatment studies were conducted on the resulting gels. Transformation to final products was studied by thermogravimetric analysis, infrared spectroscopy, and X-ray diffraction. Preliminary testing of Me leaching was also completed in quiescent water. Only a single dense form was resistant to

关键词： Sol-Gel silica glass Nuclear Waste Thermal Treatment