Electrical and flexural anisotropy in freeze tape cast stainless steel porous substrates

Freeze casting – A review of processing, microstructure and properties via the open data repository, FreezeCasting.net

“…For anisotropic pore structures, compressive strength is typically reported for loads applied parallel to the wall direction. In the cases where compressive strength is reported for loading perpendicular to the wall direction (in addition to parallel loading), anisotropic compressive strength properties, where increased strengths for parallel loading, are reported [186,308,[461][462][463][464][465]. Increased flexural [186] strength, and elastic moduli [193] are also reported for parallel loading in comparison to perpendicular loading.…”

“…Demonstrated solidification heights for this configuration range from 100 μm [180], using a combined doctor-blade/freeze-casting technique, to 9 cm [181] via traditional methods as described above. Sample areas as large as 38 x 15 cm [182] have been demonstrated via unidirectional freeze-tape-casting [182][183][184][185][186][187][188]. Anisotropic radial freeze-casting is also employed.…”

Synthesis, structure and mechanical properties of ice-templated tungsten foams

“…If a metal is desired, an additional step, often carried out prior to the fourth, consisting of chemical reduction of the ceramic to metal, usually via hydrogen, while maintaining the constructed large porosity [13][14][15][16][17] needs to be introduced. Most literature focuses on freeze casting of ceramics, but a few metallic foams have been created by freeze-casting such as copper from cupric oxide, 15 nickel from metallic nickel using a carboxymethylcellulose/gelatin mixture, 18 porous stainless steels tapes from ferritic metallic powder 19 and titanium foams from metallic titanium powder. 14,16,17 In the latter case, the oxygen content has a strong influence on the mechanical properties 16 since surface oxides of titanium are not readily reduced under H 2 .…”

Solid-state electrolyte considerations for electric vehicle batteries

“…The ice is then sublimed away, and the resulting porous structure is optionally heat-treated to sinter and strengthen the particulates in the columns while retaining the large, low tortuosity pores from the sublimed ice. It has been used successfully to prepare thick electrodes for batteries, 86 87 metal foams for solid oxide fuel cells, 88 and many other materials. 89 Porosities and pore sizes and shapes can be varied over a wide range by adjusting formulations, temperature, and other parameters.…”

“…The conductivity of these polymers can reach 10 3 -10 4 S/cm, and their unique chain-like morphology allows them to provide better conducting networks among the infiltrated active particles. 90 A variant of the freeze-casting method is freeze tape-casting (FTC), 88,91 which is scalable and ideal for making relatively thin components, ranging from as low as 5 m to several mm thick, suitable for batteries (Figure 8). For the ~100 m thin scaffolds targeted for battery applications, the use of water is preferable to organic solvents, both due to its environmental friendliness and for practical reasons (water has less tendency to evaporate prematurely during FTC processing).…”