The smoothed-particle hydrodynamics(SPH)method was introduced to simulate the quartz glass grinding process with a single grain under micrp-nano scale.To investigate the mechanism of brittle-ductile transition,such fa...The smoothed-particle hydrodynamics(SPH)method was introduced to simulate the quartz glass grinding process with a single grain under micrp-nano scale.To investigate the mechanism of brittle-ductile transition,such factors as the machin-ing depth,grinding force,maximum equivalent stress,and residual stress were analyzed.The simulation results indicate that quartz glass can be machined in a ductile mode under a certain condition.In this paper,the occurrence and propaga-tion of cracks in quartz glass at different grinding depths(0.1-1μm)are observed,and the critical depth of brittle-ductile transformation is 0.36 pum.At different grinding depths,the grinding force ratio is greater than 1.When the cutting depth is 0.4 um,the crack propagation depth is about 1.2μm,which provides a basis for the prediction of subsurface damage depth.In addition,the correctness of the simulation result was verified by carrying out scratch experiments of varying cutting depth on optical quartz glass.展开更多
The optical fiber with pure quartz core and Fluorine-doped glass cladding was made by POD (plasma outside deposition) technique in some corporations, while we used the creative technique of “overcladding F-doped tube...The optical fiber with pure quartz core and Fluorine-doped glass cladding was made by POD (plasma outside deposition) technique in some corporations, while we used the creative technique of “overcladding F-doped tube onto quartz rod in high temperature” to make the optical fiber which has the same structure as that from POD, in order to research and compare the influence factors on the loss of the fiber, our research work includes contrast experiments on coating polymers with different refractive index and the concentricity error of the fiber core and cladding. The measurement results show us that there are great differences in the loss spectra between the different fiber samples. We made analysis of it.展开更多
Production of modified liquid glass and quartz materials from kaolinite clay of Alekseev deposit of Kazakhstan was studied. The sodium liquid glass processed by kaolinite clay, with chemical composition (g/dm3): SiO2-...Production of modified liquid glass and quartz materials from kaolinite clay of Alekseev deposit of Kazakhstan was studied. The sodium liquid glass processed by kaolinite clay, with chemical composition (g/dm3): SiO2-350;Na2O-155;Al2O3-2.1;Fe2O3- 0.3, silicate module-2.33 and density-1.49 g/cm3 has been used. The sodium liquid glass complies with the Russian Interstate standard 13078-81 for sodium liquid glass.10 samples of modified liquid glass were synthesized by introducing modifiers in an amount of 4% by weight of the solution into the liquid glass. Hard quartz material produced by using synthesized modified liquid glass was obtained. It has been established that the obtained modified liquid glass from kaolinite clay can improve the strength of the quartz material for 1.6 - 3.12 times higher than the initial liquid glass. Using liquid glass modifier to the inorganic sodium nitrate (NaNO3) increases the strength 3.12 times.展开更多
An open-cell porous bulk metallic glass （BMG） with a diameter of at least 6 mm was fabricated by using an U-turn quartz tube and infiltration casting around soluble NaCI placeholders. The pore formation and glassy s...An open-cell porous bulk metallic glass （BMG） with a diameter of at least 6 mm was fabricated by using an U-turn quartz tube and infiltration casting around soluble NaCI placeholders. The pore formation and glassy structure were examined by optical microscopy （OM）, scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The results show that the pores or cells are connected to each other and the specimen is composed of a mostly glassy phase. This paper provides a suitable method for fabrication of porous BMG and BMG with larger size in diameter.展开更多
基金The authors would like to acknowledge the finan cial support from the National Natural Science Foundation of China(General Program)(No.51575083)Science Fund for Creative Research Groups(No.51621064).
文摘The smoothed-particle hydrodynamics(SPH)method was introduced to simulate the quartz glass grinding process with a single grain under micrp-nano scale.To investigate the mechanism of brittle-ductile transition,such factors as the machin-ing depth,grinding force,maximum equivalent stress,and residual stress were analyzed.The simulation results indicate that quartz glass can be machined in a ductile mode under a certain condition.In this paper,the occurrence and propaga-tion of cracks in quartz glass at different grinding depths(0.1-1μm)are observed,and the critical depth of brittle-ductile transformation is 0.36 pum.At different grinding depths,the grinding force ratio is greater than 1.When the cutting depth is 0.4 um,the crack propagation depth is about 1.2μm,which provides a basis for the prediction of subsurface damage depth.In addition,the correctness of the simulation result was verified by carrying out scratch experiments of varying cutting depth on optical quartz glass.
文摘The optical fiber with pure quartz core and Fluorine-doped glass cladding was made by POD (plasma outside deposition) technique in some corporations, while we used the creative technique of “overcladding F-doped tube onto quartz rod in high temperature” to make the optical fiber which has the same structure as that from POD, in order to research and compare the influence factors on the loss of the fiber, our research work includes contrast experiments on coating polymers with different refractive index and the concentricity error of the fiber core and cladding. The measurement results show us that there are great differences in the loss spectra between the different fiber samples. We made analysis of it.
文摘Production of modified liquid glass and quartz materials from kaolinite clay of Alekseev deposit of Kazakhstan was studied. The sodium liquid glass processed by kaolinite clay, with chemical composition (g/dm3): SiO2-350;Na2O-155;Al2O3-2.1;Fe2O3- 0.3, silicate module-2.33 and density-1.49 g/cm3 has been used. The sodium liquid glass complies with the Russian Interstate standard 13078-81 for sodium liquid glass.10 samples of modified liquid glass were synthesized by introducing modifiers in an amount of 4% by weight of the solution into the liquid glass. Hard quartz material produced by using synthesized modified liquid glass was obtained. It has been established that the obtained modified liquid glass from kaolinite clay can improve the strength of the quartz material for 1.6 - 3.12 times higher than the initial liquid glass. Using liquid glass modifier to the inorganic sodium nitrate (NaNO3) increases the strength 3.12 times.
文摘An open-cell porous bulk metallic glass （BMG） with a diameter of at least 6 mm was fabricated by using an U-turn quartz tube and infiltration casting around soluble NaCI placeholders. The pore formation and glassy structure were examined by optical microscopy （OM）, scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The results show that the pores or cells are connected to each other and the specimen is composed of a mostly glassy phase. This paper provides a suitable method for fabrication of porous BMG and BMG with larger size in diameter.
