Full definition
Corrosion-erosion wear is a complex degradation mechanism that occurs when mechanical erosion and chemical corrosion happen simultaneously, leading to significantly increased material loss compared to each factor acting independently. This phenomenon is particularly prevalent in industries such as mining, where equipment is subjected to harsh conditions involving abrasive slurries and corrosive chemicals. In slurry pumps, acid-pulp pipelines, valves, and hydrocyclones, the combined effects of these two processes can result in material loss rates that are 2 to 10 times greater than what would be expected from either erosion or corrosion alone. The underlying cause is that corrosive damage often disrupts protective layers, like passive films, and exposes fresh metal surfaces to mechanical wear, which accelerates the degradation process.
To mitigate corrosion-erosion wear, engineers often employ bimetallic materials that combine high-chromium alloys with elastomers such as rubber. These materials are designed to withstand severe conditions by providing both toughness and resistance to chemical attack. Additionally, the application of protective coatings, such as vinyl ester or epoxy novolac, can further enhance the lifespan of equipment by creating a barrier that prevents corrosive agents from reaching the metal substrate. It’s essential for engineers and maintenance personnel to understand the specific conditions under which corrosion-erosion wear occurs to select appropriate materials and protective measures effectively. Regular monitoring and maintenance are also crucial to ensure the integrity of equipment subjected to these wear mechanisms, especially in high-stakes environments like leaching and flotation plants.