Porous ceramics usually require high mechanical strength and maximized porosity simultaneously,while for conventional particle grading strategies,it is highly challenging to meet both demands.To this end,a reverse par...Porous ceramics usually require high mechanical strength and maximized porosity simultaneously,while for conventional particle grading strategies,it is highly challenging to meet both demands.To this end,a reverse particle grading strategy was developed based on the linear packing model by unusually introducing coarse particles(d_(50)=16μm)into a fine particle(d50=5μm)matrix.Following the extrusion and sintering process,tubular porous SiC ceramic supports with improved mechanical strength were successfully fabricated.The effects of coarse particles on the rheological properties of the ceramic paste and the macroscopic properties and microstructure of the SiC supports were systematically investigated.With an increase in the content of coarse SiC particles to 30 wt%,the pressure generated during extrusion decreased from 5.5±0.2 to 1.3±0.1 MPa.Notably,the bending strength of the tubular supports increased from 36.6±5.6 to 49.1±4.5 MPa when 20 wt%coarse powder was incorporated.The notably improved mechanical strength was attributed to the distribution of coarse particles that prolonged the route of crack deflection.Additionally,the optimized tubular supports had an average pore size of 1.2±0.1μm,an open porosity of 45.1%±1.6%,and a water permeability of 7163±150 L/(m^(2)·h·bar)as well as good alkali and acid corrosion resistance.Significantly,the strategy was proven to be feasible for the scale-up fabrication of 19-channel SiC tubular porous ceramic supports.展开更多
基金the financial support provided by the National Key R&D Program of China(No.2022YFB3805002)the National Natural Science Foundation of China(No.22308150)+5 种基金Jiangsu Provincial Department of Science and Technology(No.BK20232010)the Research Programs of the Science and Technology of Guangxi Zhuang Autonomous Region(No.GUIKE-AA22117015-1)the Natural Science Foundation of Jiangsu Province(No.BK20220345)the Key R&D Program of Jiangsu Province(No.BE2023360)the Key R&D Project of Nanjing Jiangbei New Area(No.ZDYF202203)the Youth Science and Technology Talents Lifting Project of Jiangsu Association of Science and Technology(No.105019ZS_007).
文摘Porous ceramics usually require high mechanical strength and maximized porosity simultaneously,while for conventional particle grading strategies,it is highly challenging to meet both demands.To this end,a reverse particle grading strategy was developed based on the linear packing model by unusually introducing coarse particles(d_(50)=16μm)into a fine particle(d50=5μm)matrix.Following the extrusion and sintering process,tubular porous SiC ceramic supports with improved mechanical strength were successfully fabricated.The effects of coarse particles on the rheological properties of the ceramic paste and the macroscopic properties and microstructure of the SiC supports were systematically investigated.With an increase in the content of coarse SiC particles to 30 wt%,the pressure generated during extrusion decreased from 5.5±0.2 to 1.3±0.1 MPa.Notably,the bending strength of the tubular supports increased from 36.6±5.6 to 49.1±4.5 MPa when 20 wt%coarse powder was incorporated.The notably improved mechanical strength was attributed to the distribution of coarse particles that prolonged the route of crack deflection.Additionally,the optimized tubular supports had an average pore size of 1.2±0.1μm,an open porosity of 45.1%±1.6%,and a water permeability of 7163±150 L/(m^(2)·h·bar)as well as good alkali and acid corrosion resistance.Significantly,the strategy was proven to be feasible for the scale-up fabrication of 19-channel SiC tubular porous ceramic supports.