Compressive strength and processing of camphene-based freeze cast calcium phosphate scaffolds with aligned pores

A meta-analysis of the mechanical properties of ice-templated ceramics and metals

“…The papers analyzed cover a variety of materials including ceramics (alumina [8–11, 26, 28, 32, 36, 38, 43, 48, 54, 58, 77, 81, 89, 102, 104, 105, 111, 112, 131, 143], zirconia [49, 80, 100, 101, 103, 125–127], silicon carbide [45, 106, 130], silicon nitride [35, 69, 72, 75, 76, 79, 84, 87, 88, 128], mullite [90, 110, 124, 137], hydroxyapatite [12, 37, 44, 52, 61, 68, 78, 86, 91, 95–98, 107, 109, 113, 115, 120, 134, 135], tri-calcium phosphate [31, 40, 56, 117, 118], lead zirconate titanate (PZT) [39, 63, 74, 82, 83, 121, 122], barium titanate [73], silica/kaolinite [47], titania [24, 29, 50, 99], zirconium diboride [51], chromium carbide [42], sialon [64, 66], lithium iron phosphate [60], yttrium orthosilicate [57, 62], cermets [116, …”

Assembling unidirectionally frozen alumina/camphene bodies for aligned porous alumina ceramics with larger dimensions

“…Regardless of the PS content, all the fabricated samples showed an aligned porous structure formed as a replica of preferentially grown camphene dendrites, 15,16 as shown in Fig. 2…”

“…The alumina powder was ball-milled with molten camphene containing various PS contents (0, 5, 10 and 20 vol.% in relation to the alumina content) using 3 wt.% of an oligomeric polyester dispersant (Hypermer KD-4, UniQema, Everburg, Belgium) at 60 • C for 24 h. The initial alumina content in the slurry was kept at 10 vol.%. The resulting slurries were then cast into ∼12.5 mm diameter polyethylene cylinders attached to a copper (Cu) plate as a cooling part and kept at 33 • C for 24 h. 16 Subsequently, the frozen samples were laminated in a polyethylene cylinder at room-temperature and pressed with finger pressure. This was followed by heat-treatment for 1 h at 33 • C that is close to the solidification of the slurry, wherein the partial re-melting of the frozen bodies could occur, which would allow the camphene dendrites at the interfaces to be merged, 14 resulting in good bonding between the laminates.…”

“…This camphene-based freeze casting which is a variant of the ice templating can also be used to produce aligned porous ceramics with a large pore size using either two-step 15 or single-step processes. 16 However, it is practically difficult to maintain the continuous preferential growth of camphene dendrites during the entire process, which would limit the degree of aligned pores. Therefore, this study proposes a novel, simple way of producing aligned porous alumina ceramics with larger dimensions by assembling unidirectionally frozen alumina/camphene bodies.…”

Production of highly aligned porous alumina ceramics by extruding frozen alumina/camphene body

“…[2][3][4] Porous materials produced using this technique can have extremely high compressive strength owing to their aligned pores. In a similar way, camphene [5][6][7] and tert-butyl alcohol (TBA) 8,9 have been used successfully as an alternative to water for the production of aligned porous materials.…”