A range of aluminium alloys and particulate reinforced aluminium metal matrix composites has been tested in an apparatus which simulates the erosive-corrosive action of a slurry. The slurry consisted of silica sand suspended in either distilled water or synthetic mine water. Several steels were also tested in order to clarify certain concepts relating to the synergistic effects of erosion and corrosion. In general both the heat-treatable and non heat-treatable aluminium alloys exhibit lower slurry erosion rates with increasing hardness and work to fracture values. The slurry erosion rates of the aluminium matrix alloys increase with increasing amounts of reinforcement particles. For the steels a good work hardening capacity and/or high hardness values are found to promote good slurry erosion resistance. All the steels exhibit lower slurry erosion rates than the aluminium alloys. A corrosion cell was developed to allow in situ electrochemical measurements to be made. The addition of corrosive ions to the distilled water results in increased material removal rates, increasing by as much as 40% for some of the aluminium alloys and 41%for the 304 stainless steel. The aluminium alloys and the steels which have increased corrosion resistance due to passivity, display poor performance under the slurry erosion-corrosion conditions tested. Paradoxically corrosion resistance was found to have a detrimental effect on the slurry erosion-corrosion resistance of a material.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:uct/oai:localhost:11427/18213 |
| Date | January 1993 |
| Creators | Bester, J A |
| Contributors | Ball, Anthony |
| Publisher | University of Cape Town, Faculty of Engineering and the Built Environment, Centre for Materials Engineering |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Master Thesis, Masters, MSc (Eng) |
| Format | application/pdf |
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