A potentially near‐net‐shape manufacturing procedure for macroporous alumina monoliths with 20%‐75% porosity was presented by gel casting of nano γ‐Al₂O₃. Although monolith obtained by nano alumina had a high surface area and low sintering temperature, an optimum fraction of micron alumina needed to be added to achieve the proper rheological and mechanical properties of slurries. The preparation parameters including alumina loading, sintering temperature, monomer concentration, and the fraction of nano alumina were investigated. The green densities ranging from 0.66 to 0.86 g cm⁻³ were obtained by raising alumina loading from 10 to 20 vol%. Depending on the monomer concentration and sintering temperature, the mean pore size ranging from 45 to 412 nm, total porosity (20%–75%), and open porosity varying from 12% to 89% were obtained. The sintered density (from 0.95 to 3.15 g cm⁻³) and compressive strength (CS) (from 4.2 to 31.46 MPa) were suitable for use in different fields.

中文翻译：

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水凝胶浇铸法制备大孔纳米氧化铝整料近净形

对于用20％-75％的孔隙率大孔氧化铝整料一个潜在的近净形状的制造过程是通过纳米的γ-Al凝胶浇铸呈现₂ ö ₃。尽管通过纳米氧化铝获得的整料具有高的表面积和低的烧结温度，但是需要添加最佳比例的微米氧化铝以实现浆料的适当的流变和机械性能。研究了氧化铝负载量，烧结温度，单体浓度和纳米氧化铝的组成等制备参数。生坯密度为0.66至0.86 g cm ^-3通过将氧化铝负载量从10体积％提高到20体积％获得。根据单体浓度和烧结温度，可以获得平均孔径范围为45至412 nm，总孔隙率（20％–75％）和开孔孔隙率范围为12％至89％。烧结密度（0.95至3.15 g cm ^-3）和抗压强度（CS）（4.2至31.46 MPa）适用于不同领域。