DESIGN, ASSEMBLY AND CHARACTERIZATION OF COMPOSITE ...

Figure 2.12 Schematic illustrations of multi-ink printing: a) the robotic gantry system
used by robocasting, b) the arrayed nozzle assembly for serial extrusion, and c) the
mixing nozzle assembly for parallel extrusion 32 . .............................................................. 24
Figure 2.13 Schematic illustrations to the concept of ink formulation induced by a) pH
change 34 , b) bridging flocculation, c) the total potential energy of interaction by two
particles with electrical double layers is shown in Figure 2.9c 37 . Flocculation is achieved
by diminishing the energy barrier, h is the separation distance. ....................................... 26
Figure 2.14 Pathway outlines for a) main chain reactions and 2) side chain reactions. 37
Figure 2.15 Sphere and plate model for examining the energy difference associated with a
curved surface 38
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Figure 2.16 Effective curvature changes for both convex and concave surfaces with
convergence toward a flat surface 38 . ................................................................................. 34
Figure 2.17 Illustration of the densification of three adjacent particles 37
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Figure 2.18 Illustration of neck growth between two spherical particles of diameter D 37 .
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Figure 2.19 Illustration of a portion of the pore and pore and grain-boundary matrix 37
.. 40
Figure 2.20 Illustration of breaking up of a cylindrical pore into a string of spherical
pores 37
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Figure 2.21 Migration of spherical pores from grain boundary to the four grain
intersections 37 . ................................................................................................................... 41
Figure 2.22 Pore detachment from grain boundary 37
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Figure 2.23 Schematic diagram of the classic liquid phase sintering stages 38 . ................. 43
Figure 2.24 Approximate time scale for liquid phase sintering, where densification occurs
by a progression of overlapping stages after the liquid forms 38 . ...................................... 44
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