Shrinkage rate controlled sintering

Figure 7.13 Flowchart of computer algorithm for shrinkage rate controlled sintering [14].

Figure 7.12 Shrinkage curves (dropping from left to right) and temperature schedules (rising from left to right) for sintering under a linear temperature control of 15°C/min (solid line) and under a linear shrinkage rate control of 0.005 in/min (dotted line). [14]...

Derive Eq. (10.38) for the shrinkage during the solution-precipitation stage of liquid-phase sintering when the phase boundary reaction is the rate controlling mechanism. 

Pyrolysis yield affects the density of the final ceramic products. Typical pyrolysis yields of carbon-based polymers are 40-60%. The change from starting polymer densities of about 1 g/cm to final densities of 2 g/cm or more commonly results in about 30% porosity. Thus, unless there is substantial shrinkage as a result of sintering or plastic deformation, a substantial amount of porosity is generated. Any densification is counterbalanced to some extent by outgassing pressure, which is determined by pyrolysis conditions, especially the rate of heating and the cross-sectional dimension, that control the rate of... 

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