The forming-regions of phosphate glasses doped with high Sm2O3 contents were studied by two step melting method. The relationship between absorption spectrum and rare earth contents was also discussed. The spectra of ...The forming-regions of phosphate glasses doped with high Sm2O3 contents were studied by two step melting method. The relationship between absorption spectrum and rare earth contents was also discussed. The spectra of BASP glasses were measured by spectrophotometer. The results show that the forming regions will shrink with the increase of Al2O3 and it is difficult to form glass when [PO4]/[AlO4] < 2. The forming regions tend to be a closed elliptical, and the intensity of characteristic absorption peak increases gradually with the increase of Sm2O3, the absorption lines broadens non-uniformly and there is approximate linear relation between optical density at the 1064 nm wavelength and Sm2O3 content.展开更多
The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by...The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by forming defects in the transitional region.In this work,the feasibility of controlling forming defects and improving the process forming limit by adjusting die parameters is explored through finite element（FE） simulation.It is found that the common cavum and folding defects in the transitional region are significantly influenced by the fillet radii of left rib and middle rib,respectively.The cavum and folding defects can be effectively controlled by increasing the fillet radii of left rib and middle rib,respectively.The process forming limits considering forming defects in the transitional region are determined by the stepwise searching method under various die parameters.Moreover,the relationship between the process forming limit and die parameters is developed through the response surface methodology（RSM）.The developed RSM models suggest that increasing the fillet radii of left and middle ribs is effective to improve the process forming limit during local loading forming of rib-web components.The results will provide technical basis for the design of die parameters and the reduction amount,which is of great importance to control forming defects and improve the process forming limit in local loading forming of Ti-alloy large-scale rib-web components.展开更多
Glass formation range of Bi2O3-B2O3-TeO2 system has been investigated （B2O3 ≤ 40 mol%）. Four glasses with compositions xBi2O3-B2O3-（70-x）TeO2 （x = 40, 50, 60 and 70 tool%） have been prepared by using melt quenc...Glass formation range of Bi2O3-B2O3-TeO2 system has been investigated （B2O3 ≤ 40 mol%）. Four glasses with compositions xBi2O3-B2O3-（70-x）TeO2 （x = 40, 50, 60 and 70 tool%） have been prepared by using melt quenching technique. The effect of Bi2O3 content on thermal stability, optical properties and structures of these four Bi2O3-B2O3-TeO2 glasses is systematically investigated by inductive coupled plasma emission spectrometer （ICP）, differential scanning calorimetry （DSC）, Raman spectra and X-ray photoelectron spectroscopy （XPS）. It is found that the density, refractive index and optical basicity increase with increasing Bi2O3. The Raman spectra and XPS spectra show that the glass network is mainly constituted by the [BiO6] octahedron, [TeO4] trigonal bipyramidal, [TeO3] trigonal pyramid, [BO3] trigonal pyramid and [B04] tetrahedron structural units. With increasing Bi2O3, the coordination number around B atom changes from 3 to 4 and [TeO4] units are converted to [TeO3] units. Bi5＋ ions may exist in Bi2O3-B2O3-TeO2 （BBT） system and their amount grows with increasing Bi2O3 content.展开更多
The formation ability and thermal stability of phosphate laser protection glass doped with high Sm2O3 content were discussed. The characteristic temperatures ( Tg, Tc, Tm) were measured by DSC and the crystallization ...The formation ability and thermal stability of phosphate laser protection glass doped with high Sm2O3 content were discussed. The characteristic temperatures ( Tg, Tc, Tm) were measured by DSC and the crystallization parameter β was calculated. The results show that the forming regions would shrink and tend to closed ellipse with increasing of Sm2O3 content. Increasing of BaO/Al2O3 ratio changes the network structure of rare earth glass and improves the thermal stability finally. However, with the increasing of Sm2O3 content, the β increases firstly and then decreases, and finally the thermal stability also increases firstly and then decreases.展开更多
基金Project supported by Research Project (A3820060136)
文摘The forming-regions of phosphate glasses doped with high Sm2O3 contents were studied by two step melting method. The relationship between absorption spectrum and rare earth contents was also discussed. The spectra of BASP glasses were measured by spectrophotometer. The results show that the forming regions will shrink with the increase of Al2O3 and it is difficult to form glass when [PO4]/[AlO4] < 2. The forming regions tend to be a closed elliptical, and the intensity of characteristic absorption peak increases gradually with the increase of Sm2O3, the absorption lines broadens non-uniformly and there is approximate linear relation between optical density at the 1064 nm wavelength and Sm2O3 content.
基金the support of the National Natural Science Foundation of China(Nos.51605388,51675433)111 Project(B08040)+2 种基金the Research Fund of the State Key Laboratory of Solidification Processing(NWPU)in China(Grant No.131-QP-2015)the Fundamental Research Funds for the Central Universitiesthe Open Research Fund of State Key Laboratory of Materials Processing and Die&Mold Technology at Huazhong University of Science and Technology
文摘The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by forming defects in the transitional region.In this work,the feasibility of controlling forming defects and improving the process forming limit by adjusting die parameters is explored through finite element（FE） simulation.It is found that the common cavum and folding defects in the transitional region are significantly influenced by the fillet radii of left rib and middle rib,respectively.The cavum and folding defects can be effectively controlled by increasing the fillet radii of left rib and middle rib,respectively.The process forming limits considering forming defects in the transitional region are determined by the stepwise searching method under various die parameters.Moreover,the relationship between the process forming limit and die parameters is developed through the response surface methodology（RSM）.The developed RSM models suggest that increasing the fillet radii of left and middle ribs is effective to improve the process forming limit during local loading forming of rib-web components.The results will provide technical basis for the design of die parameters and the reduction amount,which is of great importance to control forming defects and improve the process forming limit in local loading forming of Ti-alloy large-scale rib-web components.
基金supported by the National Natural Science Foundation of China(No.60937003)
文摘Glass formation range of Bi2O3-B2O3-TeO2 system has been investigated （B2O3 ≤ 40 mol%）. Four glasses with compositions xBi2O3-B2O3-（70-x）TeO2 （x = 40, 50, 60 and 70 tool%） have been prepared by using melt quenching technique. The effect of Bi2O3 content on thermal stability, optical properties and structures of these four Bi2O3-B2O3-TeO2 glasses is systematically investigated by inductive coupled plasma emission spectrometer （ICP）, differential scanning calorimetry （DSC）, Raman spectra and X-ray photoelectron spectroscopy （XPS）. It is found that the density, refractive index and optical basicity increase with increasing Bi2O3. The Raman spectra and XPS spectra show that the glass network is mainly constituted by the [BiO6] octahedron, [TeO4] trigonal bipyramidal, [TeO3] trigonal pyramid, [BO3] trigonal pyramid and [B04] tetrahedron structural units. With increasing Bi2O3, the coordination number around B atom changes from 3 to 4 and [TeO4] units are converted to [TeO3] units. Bi5＋ ions may exist in Bi2O3-B2O3-TeO2 （BBT） system and their amount grows with increasing Bi2O3 content.
基金Project supported by the Senior Intellectuals Fund of Jiangsu University (05JDGO46)"333 Project" Fund of Jiangsu Province (JS2001-78)
文摘The formation ability and thermal stability of phosphate laser protection glass doped with high Sm2O3 content were discussed. The characteristic temperatures ( Tg, Tc, Tm) were measured by DSC and the crystallization parameter β was calculated. The results show that the forming regions would shrink and tend to closed ellipse with increasing of Sm2O3 content. Increasing of BaO/Al2O3 ratio changes the network structure of rare earth glass and improves the thermal stability finally. However, with the increasing of Sm2O3 content, the β increases firstly and then decreases, and finally the thermal stability also increases firstly and then decreases.
