DESIGN, ASSEMBLY AND CHARACTERIZATION OF COMPOSITE ...

near-dense composite material. Compared with plasma spraying, the principal limitation
of this process for composite fabrication is that only the metal phase is melted.
Consequently, the volume fraction of the more refractory phase is limited by its packing
density and the volume of the metal phase sprayed between particles. Thus, phase volume
fraction of the refractory phase incorporated has a maximum in the vicinity of 30-40 %.
Electroforming Process has been used for fabrication of metal/metal and
metal/ceramic graded materials. An electrolytic cell featuring dual anodes of Cu and Ni,
as shown in Figure 2.37, is used to deposition graded metal foils. Ceramic reinforcement
may be incorporated by adding ceramic particles to the electrolytic solution, and
incorporating these particles into the growing metal layer during electro-deposition.
Figure 2.37 Schematic illustration of the apparatus for the electro-deposition of graded
bimetallic layers. 44
Vapor Deposition Process has the advantage that very thin layers may be
produced. With steep composition gradients, however, a reduced stability of the FGM at
elevated temperature may result. 83 Various deposition techniques are used for fabrication
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