Microstructure of the pyrocarbon matrix in carbon/carbon composites

Influence of surface on chemical kinetic of pyrocarbon deposition obtained by propane pyrolysis

“…The smooth laminar (SL) microtexture of pyrocarbon was observed by PLOM with these conditions. This observation is in agreement with other studies [17,18,20].…”

“…Some results obtained during the study of the influence of the A/V ratio on the kinetics of deposition are in good agreement with the results obtained by other laboratories even if our experimental conditions were rather different [3][4][5][6][7][8][16][17][18][19][20]. For example, we found that the increase in A/V leads to a reduction in the concentration of the gas species and that the reduction is much more important for unsaturated species.…”

“…Secondly, the gaseous composition is the same in its whole volume, thus the concentrations measured at the outlet of the reactor are the same ones as those close to the surface of the carbon fibers. This last point is important since most of the previous studies were preformed in a tubular reactor, which presents the drawback of generating a profile of gaseous species concentration along the reactor axis [16][17][18][19]. So it is not possible to really know the composition of the gaseous phase near the fibers of carbon during the pyrolysis.…”

Pyrolysis of propane for CVI of pyrocarbon

“…It is an important problem, which is related to the very slow kinetic of the deposition, causing high costs of manufacture. In addition, modification of the operating conditions or the use of different kind of reactants can lead to various nanotextural forms with different mechanical and thermal properties of the C/C composite [1][2][3][4][5].…”

Mechanical properties of C/C composites processed by wet impregnation and P-CVI methods

“…Methods of liquid impregnation and various modifications of CVD method are being commonly used as basic techniques of densification of porous composite matrix after first thermal treatment of polymer substrate. The principles of both techniques in application to C/C composites are well defined and known [10][11][12], however intensive works are still being carried out related to modification and optimization of the process itself, considering many factors affecting the porous substrate, gas phase carbon precursors, as well as modifications of construction of the reactor itself where the process takes place [11][12][13][14].…”