Author: VV Tcherdyntsev, SD Kaloshkin, EV Shelekhov, AI Salimon, S. Sartori, G. Principi
Institute: Materials and INFM Sector, Department of Mechanical Engineering, University of Padua, via Marzolo 9, 35131 Padua, Italy
The formation of a quasicrystalline phase in the mechanically alloyed Al–Cu–Fe system is an interesting area of study in materials science. The processes occurring in this system depend on the level of mechanical action, which leads to significant changes in the microstructure of the alloys. Mechanical alloying, accompanied by high pressures and temperatures, promotes the intensification of diffusion processes and the formation of new crystal lattices.
Quasi-crystalline phases are characterized by unique properties, such as low thermal conductivity and high hardness, which makes them promising for use in various industries, including mechanical engineering and aerospace. When alloying the Al-Cu-Fe system, it is important to consider the ratio of components, as well as the parameters of mechanical action, which can significantly affect the final properties of the material.
A general understanding of the mechanisms of formation of quasicrystalline structure requires a multifaceted approach, including both experimental and theoretical studies. This opens up new horizons for the development of materials with specified properties and increased resistance to external influences.
Over the past twenty years, quasicrystal (QC)-based materials have been actively studied due to their unique properties and promising application possibilities. The discovery of quasicrystalline alloys, like the emergence of amorphous materials, forced us to reconsider traditional views on the structure of solids. Since this important discovery, a number of stable and metastable quasicrystals have been obtained in various binary and multicomponent systems. Typically, quasicrystals are formed on the basis of Al, Mg, Zn, Zr and Ti.
The electronic structure of QC phases gives them a number of interesting properties that can be useful in various technologies. The main characteristics include mechanical properties such as high strength (measured up to 13 GPa, as opposed to 7–8 GPa for martensitic steels), hardness, and wear resistance. However, increasing the temperature significantly reduces the strength of quasicrystals.
In addition, QC phases have good antifriction properties due to their high hardness and low friction coefficient, which is associated with their low surface energy of 28 mJ/m². Unlike fluorocarbon polymers, which have a surface of 18 mJ/m², QC materials have strong interatomic bonds, which implies high corrosion resistance.
The main disadvantages of quasicrystals remain high brittleness and limited manufacturability. However, they show promise as a reinforcing phase for composites. Research shows the possibility of using and producing stable QC alloys using mechanical alloying methods, which allows for an expansion of the composition range and production efficiency.