Quasi-crystalline composite coatings based on the Al–Cu–Fe system are promising materials for protecting surfaces from wear due to their high hardness and oxidation resistance. However, the behavior of these coatings under abrasive wear conditions requires detailed study, given the complexity of their microstructure and interaction with abrasive particles.
Abrasive wear of quasi-crystalline composites is a complex process involving several mechanisms such as micro-cutting, plastic deformation, brittle fracture and particle ejection. The effectiveness of wear protection is determined by the ratio of the hardness of the composite and abrasive particles, as well as the strength of the bond between the quasi-crystalline phase and the matrix.
Quasicrystals, a relatively recently discovered family of materials, are distinguished by their unique structure at the atomic level and valuable physical and chemical properties. Their natural fragility hinders their widespread use, limiting their use mainly to surface layers. This study is devoted to the study of the effect of Fe–Al plastic phase additives (in the range of 0–100 vol.%) on the abrasive wear resistance of quasicrystalline Al–Cu–Fe coatings.
The coating process was carried out using the plasma spraying method. The introduction of individual Fe–Al particles into the structure of the quasi-crystalline matrix helps to increase the resistance of the coating to abrasive wear. It is noteworthy that the minimum addition of the Fe–Al phase (for example, 1 vol.%) leads to the formation of a coating with the highest wear resistance. The discussion of the wear resistance of quasi-crystalline and composite coatings is carried out taking into account the nature of wear and the hardness indicators of the coating.
The microstructure of the coating, including the size and distribution of quasicrystalline particles, has a significant effect on its wear resistance. A more uniform distribution of particles and their smaller size help to reduce local stress concentrations and increase resistance to fracture. The introduction of hardening additives, such as oxides or carbides, can further increase the hardness and wear resistance of the coating.
Mechanisms of abrasive wear can vary depending on operating conditions, including load, sliding speed, size and hardness of abrasive particles. Understanding these mechanisms allows the design and structure of coatings to be optimized to achieve maximum wear resistance in specific application conditions.
Author: DJ Sordelet, MF Besser, JL Logsdon
Institute: Metallurgy and Ceramics Program, Ames Laboratory, Iowa State University, Ames, Iowa 50014, USA, Department of Materials Science and Engineering, Iowa State University, Ames, IA 50014, USA, Department of Mechanical Engineering, Iowa State University, Ames, IA 50014, USA