DESIGN, ASSEMBLY AND CHARACTERIZATION OF COMPOSITE ...

Figure 3.9 Thermogravimetric analysis of oxidation of as-dried carbon black gel in CO2:
(a) TGA plot (b) DTA plot. ............................................................................................. 105
Figure 3.10 Arrhenius plot for the oxidation of carbon black ink in CO2 ...................... 106
Figure 3.11 a) Non-space filling frame lattice printed with BT and carbon black inks; b)
BT structure after burnout of carbonaceous content; c) sintered BT structures positioned
against each other; d) a sintered non-space filling frame HA lattice, and e) a periodic BT
structure after burnout of carbonaceous content ............................................................. 110
Figure 4.1 Temperature profile for sintering of nickel. .................................................. 118
Figure 4.2 Apparent viscosity of φsolids = 0.50 nickel suspension at shear rate γ� = 1 s -1
Figure 4.3 SEM image of ENP 800 nickel powder ........................................................ 120
Figure 4.4 Shear modulus G’ vs. shear stress τ of Nickel gels (φsolids = 0.472) with
varying flocculant (PAA) concentration. ........................................................................ 122
Figure 4.5 Thermogravimetric analysis of thermal degradation Darvan 821A, PEI-25K,
and HMPC ...................................................................................................................... 125
Figure 4.6 Sintered Ni structures: a) top view of box-shaped and cylindrical lattices, and
b) solid cylindrical rods; the one on the right has a matte cross-section after etching with
10% Marble's reagent. (Scale unit: mm) ......................................................................... 127
Figure 4.7 Grain structures of sintered nickel samples: a) 99.2% dense sample from φsolids
= 0.472 nickel ink sintered at 900 °C for 2 hours; and b) 92.0% dense sampl from φsolids =
0.43 nickel ink sintered at 1000 °C, 2 hours; many pores are trapped in the Ni grains. . 129
Figure 4.8 Scanning electron micrograph of the pyramid indent on 99.2% dense nickel
specimens. ....................................................................................................................... 131
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