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Alumina (Al2O3) microfiltration membranes with holey interior structure exhibit the combined desirable properties of both superior permeability and good retention performance. These membranes are purposely made to consist of a holey intermediate layer with a thickness in the range 12.9‐15.5 μm and a top filtration layer of very thin thickness in the range 1.8‐2.8 μm, fabricated by cosintering with sacrificial carbon (C) particles. The holey structure in the intermediate layer, which can be well controlled by regulating the amount of C particles added to Al2O3 particles, contains plenty of holes of 1‐5 μm in size, thereby possessing much reduced water flow resistance. The thin top filtration layer, which contains uniformly distributed nanopores of 90‐100 nm in size, functions as the selective layer, thereby ensuring a good retention performance. At the C particle content of 30 wt. %, the Al2O3 membrane with holey interior structure demonstrates a super‐high pure water flux (3358 Lm‐2h‐1), which is almost twice that of the membrane without holey interior structure (1697 Lm‐2h‐1), while the mechanical strength and retention performance are well maintained. [ABSTRACT FROM AUTHOR]

B4C-TiB2-SiC composites toughened by composite structural toughening phases, which are the units of (TiB2-SiC) composite, were fabricated through reactive hot pressing with B4C, TiC, and Si as raw materials. The units of (TiB2-SiC) composite with the size of 10-20 μm are composed of interlocking TiB2 and SiC with the size of 1-5 μm. The addition of TiC and Si can effectively promote the sintering of B4C ceramics. The relative densities of all the B4C composites with different contents of TiB2 and SiC are close to completely dense (98.9%-99.4%), thereby resulting in superior hardness (33.1-36.2 GPa). With the increase in the content of TiB2 and SiC, the already improved fracture toughness of the B4C composite continuously increases (5.3-6.5 MPa·m1/2), but the flexure strength initially increases and then decreases. When cracks cross the units of the (TiB2-SiC) composite, the cracks deflect along the interior boundary of TiB2 and SiC inside the units. As the crack growth path is lengthened, the crack propagation direction is changed, thereby consuming more crack extension energy. The cumulative contributions improve the fracture toughness of the B4C composite. Therefore, the composite structural toughening units of the (TiB2-SiC) composite play an important role in reinforcing the fracture toughness of the composites. [ABSTRACT FROM AUTHOR]