针对光固化Al2O3陶瓷在脱脂烧结后易形成孔洞、力学性能差的问题,系统研究了石墨烯添加对陶瓷浆料流变性、沉降性、固化行为及烧结体力学性能的影响。采用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)对Al2O3粉体进行表面改性,并加入不同含...针对光固化Al2O3陶瓷在脱脂烧结后易形成孔洞、力学性能差的问题,系统研究了石墨烯添加对陶瓷浆料流变性、沉降性、固化行为及烧结体力学性能的影响。采用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)对Al2O3粉体进行表面改性,并加入不同含量的石墨烯,制备高固相、低粘度的光固化浆料。通过傅里叶红外光谱、旋转流变仪、沉降试验及Beer-Lambert模型分析,优化了浆料配方与光固化工艺参数。结果表明:当KH560含量为2.5wt%、石墨烯含量为0.01wt%时,浆料粘度最低、沉降分层最少;在曝光时间4 s条件下,添加0.01wt%石墨烯的浆料透射深度为382μm,临界曝光能量为44.3 m J/cm2。经1750℃烧结后,陶瓷零件致密度达99.7%,弯曲强度为27.61 MPa,维氏硬度为13.45GPa。石墨烯通过位阻效应及裂纹偏转机制有效促进了烧结致密化并改善了力学性能。本研究为光固化增材制造高致密、高性能氧化铝陶瓷提供了试验依据。展开更多
The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al2O3-coated polyimide(AO/PI)porous film as ...The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al2O3-coated polyimide(AO/PI)porous film as a high-strength substrate to support fast-ion-conducting polymer-in-salt(PIS)solid-state electrolytes,aiming to suppress lithium dendrite growth and improve full-cell performance.The Al2O3coating layer not only refines the wettability of polyimide porous film to PIS,but also performs as a high modulus protective layer to suppress the growth of lithium dendrites.The resulting PI/AO@PIS exhibits a small thickness of only 35μm with an outstanding tensile strength of 11.3 MPa and Young's modulus of 537.6 MPa.In addition,the PI/AO@PIS delivers a high ionic conductivity of 0.1 m S/cm at 25°C.As a result,the PI/AO@PIS enables symmetric Li cells to achieve exceptional cyclability for over 1000 h at 0.1 m A/cm2without noticeable lithium dendrite formation.Moreover,the PI/AO@PIS-based LiFePO4||Li full cells demonstrate outstanding rate performance(125.7 m Ah/g at 5 C)and impressive cycling stability(96.1%capacity retention at 1 C after 200 cycles).This work highlights the efficacy of enhancing the mechanical properties of polymer matrices and extending cell performance through the incorporation of a dense inorganic interface layer.展开更多
FeAl intermetallic compound with different contents of rare earth oxide La2O3 addition was prepared by hot pressing the mechanically alloyed powders.Effect of La2O3 on microstructure and high-temperature wear property...FeAl intermetallic compound with different contents of rare earth oxide La2O3 addition was prepared by hot pressing the mechanically alloyed powders.Effect of La2O3 on microstructure and high-temperature wear property of the sintered FeAl samples was investigated in this paper.The results showed that 1 wt.% La2O3 addition could refine the microstructure and increase the density of the FeAl intermetallic compound,and correspondingly improved the high-temperature wear resistance.SEM and EDS analyses of the wo...展开更多
A simple modified analytic EAM model for bcc Fe and fcc Al was used to calculate the lattice constant and elastic constants of B2 FeAl and DO3 Fe3Al alloys. The formation energies of vacancy and antisite were also cal...A simple modified analytic EAM model for bcc Fe and fcc Al was used to calculate the lattice constant and elastic constants of B2 FeAl and DO3 Fe3Al alloys. The formation energies of vacancy and antisite were also calculated. The present calculations are in agreement with the experimental data and the theoretical results obtained by other authors.展开更多
In order to investigate the effects of oxide particles on the high-temperature resistance and ablation performance of ceramicizable phenolic resin composites,three types of quartz fiber-reinforced ceramicizable phenol...In order to investigate the effects of oxide particles on the high-temperature resistance and ablation performance of ceramicizable phenolic resin composites,three types of quartz fiber-reinforced ceramicizable phenolic resin composites were prepared using MgO particles or Al2O3 particles as the second-phase oxides and ZrB2 particles as the high-temperature ceramic filler,through a mold pressing process.The enhancement effects and mechanisms of the added second-phase oxides on the high-temperature resistance and ablation performance of the composites were discussed and analyzed through high-temperature testing,phase characterization,oxyacetylene testing,and microstructure characterization.The results show that ZrB2 particles oxidize to form ZrO2 and B2O3 in an oxygen-rich high-temperature environment.The added second-phase oxide particles can react with B2O3 to form corresponding borates,thereby strengthening the matrix.After treatment at 800℃,the flexural strength of the ZrB2-MgO quartz fiber-reinforced phenolic resin composite(QFPR/ZM)increased by 55.3%compared to the ZrB2 quartz fiber-reinforced phenolic resin composite(QFPR/Z).The oxyacetylene ablation performance of the composites with added oxide particles was significantly influenced by the generated borates.Mg3B2O6 has a higher high-temperature viscosity than Al18B4O33 at high temperatures,resulting in a lower linear ablation rate for QFPR/ZM compared to the ZrB2-Al2O3 quartz fiber-reinforced phenolic resin composite(QFPR/ZA).展开更多
Al2O3f/Al2O3 ceramic matrix composites(CMC)are promising candidate materials of blades and combustor liners of future gas turbines in light of their higher temperature capability,higher environmental stability and oxi...Al2O3f/Al2O3 ceramic matrix composites(CMC)are promising candidate materials of blades and combustor liners of future gas turbines in light of their higher temperature capability,higher environmental stability and oxidizing-free capacity[1–3].Nevertheless,grain growth,sintering and creep deformation at high operation temperatures are still serious problems for Al2O3f/Al2O3 ceramic matrix composites,which can lead to a reduction in the strength and damage tolerance[2].Moreover,Al2O3 can be corroded by the high temperature water vapor in combustion environments and yields volatile products,such as Al(OH)3[4].Consequently,environmental barrier coatings(EBCs)are necessary for Al2O3f/Al2O3 ceramic matrix composites,which can protect Al2O3f/Al2O3 CMC from high temperature and flowing combustion gas corrosion and thus increase the high temperature capability and the service life of components.展开更多
The catalyst of CUOx/Al2O3 was prepared by the dipping-sedimentation method using y-Al2O3 as a supporter.CuO and Cu2O were loaded on the surface of Al2O3,characterized by X-ray diffraction(XRD)and X-ray photoelectron ...The catalyst of CUOx/Al2O3 was prepared by the dipping-sedimentation method using y-Al2O3 as a supporter.CuO and Cu2O were loaded on the surface of Al2O3,characterized by X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).In the presence of CuOx/Al2O3,the microwave-induced chlorine dioxide(ClO2)catalytic oxidation process was conducted for the treatment of synthetic wastewater containing 100 mg/L phenol.The factors influencing phenol removal were investigated and the results showed that microwave-induced C102-CuOx/ml203 process could effectively degrade contaminants in a short reaction time with a low oxidant dosage,extensive pH range.Under a given condition(ClO2 concentration 80 mg/L,microwave power 50 W,contact time 5 latin,catalyst dosage 50 g/L,pH 9),phenol removal percentage approached 92.24%,corresponding to 79.13%of CODcr removal.The removal of phenol by microwave-induced ClO2-CuOx/Al2O3 catalytic oxidation process was a complicated non-homogeneous solid/water reaction,which fitted pseudo-first-order by kinetics.Compared with traditional ClO2 oxidation,ClO2 catalytic oxidation and microwave-induced ClO2 oxidation,microwave-induced ClO2 catalytic oxidation system could significantly enhance the degradation efficiency.It provides an effective technology for the removal of phenol wastewater.展开更多
摘要针对光固化Al2O3陶瓷在脱脂烧结后易形成孔洞、力学性能差的问题,系统研究了石墨烯添加对陶瓷浆料流变性、沉降性、固化行为及烧结体力学性能的影响。采用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)对Al2O3粉体进行表面改性,并加入不同含量的石墨烯,制备高固相、低粘度的光固化浆料。通过傅里叶红外光谱、旋转流变仪、沉降试验及Beer-Lambert模型分析,优化了浆料配方与光固化工艺参数。结果表明:当KH560含量为2.5wt%、石墨烯含量为0.01wt%时,浆料粘度最低、沉降分层最少;在曝光时间4 s条件下,添加0.01wt%石墨烯的浆料透射深度为382μm,临界曝光能量为44.3 m J/cm2。经1750℃烧结后,陶瓷零件致密度达99.7%,弯曲强度为27.61 MPa,维氏硬度为13.45GPa。石墨烯通过位阻效应及裂纹偏转机制有效促进了烧结致密化并改善了力学性能。本研究为光固化增材制造高致密、高性能氧化铝陶瓷提供了试验依据。
基金the financial support from the 261Project of MIIT and Natural Science Foundation of Jiangsu Province(No.BK20240179)。
摘要The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al2O3-coated polyimide(AO/PI)porous film as a high-strength substrate to support fast-ion-conducting polymer-in-salt(PIS)solid-state electrolytes,aiming to suppress lithium dendrite growth and improve full-cell performance.The Al2O3coating layer not only refines the wettability of polyimide porous film to PIS,but also performs as a high modulus protective layer to suppress the growth of lithium dendrites.The resulting PI/AO@PIS exhibits a small thickness of only 35μm with an outstanding tensile strength of 11.3 MPa and Young's modulus of 537.6 MPa.In addition,the PI/AO@PIS delivers a high ionic conductivity of 0.1 m S/cm at 25°C.As a result,the PI/AO@PIS enables symmetric Li cells to achieve exceptional cyclability for over 1000 h at 0.1 m A/cm2without noticeable lithium dendrite formation.Moreover,the PI/AO@PIS-based LiFePO4||Li full cells demonstrate outstanding rate performance(125.7 m Ah/g at 5 C)and impressive cycling stability(96.1%capacity retention at 1 C after 200 cycles).This work highlights the efficacy of enhancing the mechanical properties of polymer matrices and extending cell performance through the incorporation of a dense inorganic interface layer.
基金supported by the National Natural Science Foundation of China (50575034)
摘要FeAl intermetallic compound with different contents of rare earth oxide La2O3 addition was prepared by hot pressing the mechanically alloyed powders.Effect of La2O3 on microstructure and high-temperature wear property of the sintered FeAl samples was investigated in this paper.The results showed that 1 wt.% La2O3 addition could refine the microstructure and increase the density of the FeAl intermetallic compound,and correspondingly improved the high-temperature wear resistance.SEM and EDS analyses of the wo...
摘要A simple modified analytic EAM model for bcc Fe and fcc Al was used to calculate the lattice constant and elastic constants of B2 FeAl and DO3 Fe3Al alloys. The formation energies of vacancy and antisite were also calculated. The present calculations are in agreement with the experimental data and the theoretical results obtained by other authors.
基金Funded by the Natural Science Foundation of Hubei Province(No.2024AFB833)。
摘要In order to investigate the effects of oxide particles on the high-temperature resistance and ablation performance of ceramicizable phenolic resin composites,three types of quartz fiber-reinforced ceramicizable phenolic resin composites were prepared using MgO particles or Al2O3 particles as the second-phase oxides and ZrB2 particles as the high-temperature ceramic filler,through a mold pressing process.The enhancement effects and mechanisms of the added second-phase oxides on the high-temperature resistance and ablation performance of the composites were discussed and analyzed through high-temperature testing,phase characterization,oxyacetylene testing,and microstructure characterization.The results show that ZrB2 particles oxidize to form ZrO2 and B2O3 in an oxygen-rich high-temperature environment.The added second-phase oxide particles can react with B2O3 to form corresponding borates,thereby strengthening the matrix.After treatment at 800℃,the flexural strength of the ZrB2-MgO quartz fiber-reinforced phenolic resin composite(QFPR/ZM)increased by 55.3%compared to the ZrB2 quartz fiber-reinforced phenolic resin composite(QFPR/Z).The oxyacetylene ablation performance of the composites with added oxide particles was significantly influenced by the generated borates.Mg3B2O6 has a higher high-temperature viscosity than Al18B4O33 at high temperatures,resulting in a lower linear ablation rate for QFPR/ZM compared to the ZrB2-Al2O3 quartz fiber-reinforced phenolic resin composite(QFPR/ZA).
基金financial supported by the National Natural Science Foundation of China(Nos.51672064 and U1435206).
摘要Al2O3f/Al2O3 ceramic matrix composites(CMC)are promising candidate materials of blades and combustor liners of future gas turbines in light of their higher temperature capability,higher environmental stability and oxidizing-free capacity[1–3].Nevertheless,grain growth,sintering and creep deformation at high operation temperatures are still serious problems for Al2O3f/Al2O3 ceramic matrix composites,which can lead to a reduction in the strength and damage tolerance[2].Moreover,Al2O3 can be corroded by the high temperature water vapor in combustion environments and yields volatile products,such as Al(OH)3[4].Consequently,environmental barrier coatings(EBCs)are necessary for Al2O3f/Al2O3 ceramic matrix composites,which can protect Al2O3f/Al2O3 CMC from high temperature and flowing combustion gas corrosion and thus increase the high temperature capability and the service life of components.
基金Project supported by the National Nature Science Foundation of China(No.50678045).
摘要The catalyst of CUOx/Al2O3 was prepared by the dipping-sedimentation method using y-Al2O3 as a supporter.CuO and Cu2O were loaded on the surface of Al2O3,characterized by X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).In the presence of CuOx/Al2O3,the microwave-induced chlorine dioxide(ClO2)catalytic oxidation process was conducted for the treatment of synthetic wastewater containing 100 mg/L phenol.The factors influencing phenol removal were investigated and the results showed that microwave-induced C102-CuOx/ml203 process could effectively degrade contaminants in a short reaction time with a low oxidant dosage,extensive pH range.Under a given condition(ClO2 concentration 80 mg/L,microwave power 50 W,contact time 5 latin,catalyst dosage 50 g/L,pH 9),phenol removal percentage approached 92.24%,corresponding to 79.13%of CODcr removal.The removal of phenol by microwave-induced ClO2-CuOx/Al2O3 catalytic oxidation process was a complicated non-homogeneous solid/water reaction,which fitted pseudo-first-order by kinetics.Compared with traditional ClO2 oxidation,ClO2 catalytic oxidation and microwave-induced ClO2 oxidation,microwave-induced ClO2 catalytic oxidation system could significantly enhance the degradation efficiency.It provides an effective technology for the removal of phenol wastewater.