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Machinery and equipment used in abrasive environments, such as the mining industry, suffer from severe wear. In order to understand wear and to prolong the life time of the machinery, it is important to understand how materials respond to wear depending on the environmental and tribological conditions imposed. This paper exposes a comparative study between the influence of two abrasive environments (dry and slurry) on hard particle coatings and steels. To study this, the 3-body wear behaviour was evaluated in a dry environment using a continuous abrasion test (CAT) and in a slurry environment using a slurry steel wheel abrasion test (SSWAT) method. Both tests are capable of experimentally modelling the high stress wear at 45 N and 216 N, using quartz sand as an abrasive. The tests were performed on two types of coatings processed by sintering and hardfacing and martensitic steel was used as a reference. The wear was indicated as volume loss by measuring the samples before and after the tests. Furthermore, the specific wear energy was calculated in order to have a fundamental understanding about the material's response to wear. A correlation between the wear rate and the particle brakeage index (PBI) was done for the dry conditions using different loads, in order to explain the interdependence between the two parameters and the change in the wear mechanism between the two loads. The influence of load on the wear of the materials showed different wear mechanisms on coatings compared to the steel in the same environmental conditions. However, a change in wear mechanism at different load levels was observed, which might be directly dependent on the change of the particle's motion from sliding to rolling combined with the change in their shape and size. The results showed that the need to study the influence of different abrasive conditions on the material wear is crucial in order to improve the lifetime and the cost efficiency of the machinery used in such environments. The hard-particle coatings showed comparatively low wear rates promising a great potential in improving the lifetime of industrial equipments in different environments. |
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