This work is a preliminary attempt to study the effect between thermal shock and
abrasive wear in WC-Co alloys. This was done by evaluating the thermal shock
resistance of a WC-12wt%Co mining grade as a function of temperature, number
of thermal shock cycles and making comparisons between the abrasive wear
responses of samples subjected to thermal shock and samples not subjected to
thermal shock.
A furnace was designed for the thermal shock treatments. Abrasive wear tests
were performed on a 2-body sliding wear apparatus using 80-grit SiC abrasive
paper as a counter-face. Stereo and electron microscopy as well as microprobe
techniques were used to analyse the effects of thermal shock. It is confirmed that
thermal shock has a negative effect on the wear rate of WC-12wt%Co. The results
showed an initial high mass loss rate during abrasive wear testing, which
increased with increasing temperature and a decrease in wear rate with time until
the wear rates converged for all samples. The surface analysis after thermal shock
indicated voids on and below the surface, stained surfaces, a thin oxide layer and
the possibility of WC decarburization which accelerated the wear response.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:wits/oai:wiredspace.wits.ac.za:10539/6798 |
| Date | 25 March 2009 |
| Creators | Makgere, Machoene Frederick |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | application/pdf, application/pdf, application/pdf, application/pdf, application/pdf, application/pdf, application/pdf, application/pdf, application/pdf |
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