Pore structure, porosity and compressive strength of highly porous reaction-bonded silicon nitride ceramics with various grain morphologies

Tailorable Micelle Morphology in Self-Assembling Block Copolymer Gels for Templating Nanoporous Ceramics

“…The above results indicate that porosity can be tuned in the resulting ceramics, which may be useful for catalysis, , thermal, , and structural applications. − The ability to change the porosity and the size of the pores using the same system will be especially helpful for optimizing ceramic nanostructures for desired applications. , We expect that porosity and strut geometry will have a pronounced effect on the mechanical properties of ceramic films, , which we will explore and report in a forthcoming publication.…”

“…In addition to the assembly of presynthesized nanoparticles, BCPs have found use in templating preceramic polymers (PCPs). ,,− PCPs contain both organic and inorganic constituents (e.g., C and Si) and convert to an inorganic material (e.g., silicon carbide (SiC)), upon heating (i.e., pyrolysis). As macromolecules, PCPs are easily processed: they can be additively manufactured, infiltrated into composites, and mixed into solvents with other polymer systems (i.e., BCPs). − Such polymer-derived ceramics are of interest for a diverse set of applications ranging from structural − to catalytic. , Though they provide impressive nanostructured ceramics, many of these prior investigations utilize batch-scale custom BCPs, making the transition of these fundamental studies to large-scale applications challenging.…”

Effects of surfactant and particle size on the microstructure and strength of Si3N4 foams with high porosity

“…Meanwhile, with the Si 3 N 4 particle size decreases from 1.02 to 0.23 μm, the compressive strength increases evidently from 1.24MPa to 3.51MPa. Such results could also be attributed to the higher aspect ratio of β-Si 3 N 4 grains aforementioned [29][30][31] .…”

A comparative study on nitridation mechanism and microstructural development of porous reaction bonded silicon nitride in the presence of CaO, MgO and Al2O3

“…For instance, spherical pores with ≈53 vol.% porosity and rod-like pores with ≈42 vol.% porosity have been developed using benzoic acid balls [20] and organic whiskers [21], respectively. Similarly, the structure and size of cavities can be affected by the morphology of the RBSN grains constructing the skeletal part [22,23].…”

“…Besides the two morphologies of α-matte grains and elongated β-rods, Si 3 N 4 may form whiskers randomly distributed throughout the pore channels [24,25]. These interlocked whiskers with high aspect ratio improve the mechanical strength and fracture toughness of the load-bearing materials while decreasing the interconnectivity of channels and permeability and size of pores in filtration membranes [22,26,27]. Growth of granular grains on the pore walls in contrast leads to the formation of large cavities and enhanced channel interconnectivity suitable for interpenetrating ceramic-metal composites [22,26,27].…”