A new process, the DIMOX$ rm sp{TM}$ Process, for making ceramic matrix and metal matrix composites was developed and commercialized by Lanxide Corporation. This technology is based on the use of a unique directed-metal oxidation process to grow ceramic matrices around pre-placed composite fillers or reinforcements. This thesis attempts to offer a good understanding of the mechanism of the process, as well as the effects of the processing parameters on the process, especially in the presence of a reinforcing material. Metal-ceramic matrix composites were grown into four different SiC powders by the directed oxidation of aluminum alloys in air at various temperatures. Microstructure, microstructural evolution, and growth kinetic studies were performed on these composites as a function of alloy compositions, processing temperature, and preform size. The results are then compared to those of composites processed without SiC-reinforcing particles. / The microstructure of the resulting composites consists of three phases: the SiC preform, a continuous $ alpha$-$ rm Al sb2O sb3$ matrix, and a network of unoxidized metal. The microstructural evolution for composites without SiC starts with an incubation period of variable length. The incubation time decreases with increase in the processing temperature and with increase in the alloy silicon content. The addition of silicon in the alloy decrease the viscosity of the melt and therefore increases the rate of metal supply to the reaction front. However increasing the magnesium content resulted only in a slight decrease of the length of the incubation period. / For composites processed with SiC particles, the growth started immediately after introducing the alloy into the hot zone of the furnace. The incubation time was very short and was not sensitive to changes in either temperatures or alloy composition. The preform does not show any evidence of degradation by the molten alloy, however the growth front tends to climb up the surface of the particles. The composite growth rate increased with decreasing in the preform particle size. / The oxidative formation of $ rm Al sb2O sb3$ matrix composites using Al-Mg and Al-Mg-Si alloys exhibits a linear type of kinetics in both the presence and absence of SiC preforms with an activation energy of 224 kJ/mol.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.42047 |
| Date | January 1996 |
| Creators | Guermazi, Mohamed. |
| Contributors | Drew, Robin A. L. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Mining and Metallurgical Engineering.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001565027, proquestno: NQ29952, Theses scanned by UMI/ProQuest. |
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