The introduction of new materials with unique properties is a key factor in the development of modern technologies. Quasicrystals, which have an aperiodic atomic structure, are a class of materials with exceptional characteristics such as high hardness, low friction coefficient, and good corrosion resistance. However, their brittleness limits their widespread use. One promising approach to improving the mechanical properties of quasicrystals is their reinforcement with carbon nanostructures.
To create the nanocomposite material, a high-intensity ball mill was used to grind hexagonal carbon and a precise mixture of AlCuFe, forming quasicrystals (QC). X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the structure and morphology of the ground powders.
XRD data showed that as the grinding time increases, the diffraction peaks of the quasi-crystalline phase broaden, while the peaks of hexagonal carbon gradually weaken, indicating nanostructuring of the material. Raman spectra confirmed the presence of nanocrystalline carbon particles acting as a reinforcing component in the composite.
TEM observations confirmed that high-energy ball milling effectively creates nano-quasicrystalline material with highly deformed onion-shaped carbon particles (UDCs) in a relatively short processing time. SEM showed the grinding of powder particles during the mechanical action.
However, TEM revealed that the particle size of the CC is much larger than that of the UCCL, indicating the prospect of achieving good dispersion and uniform distribution of the reinforcing agent. The diameter of the UCCL varies from 4 to 12 nm, and the number of graphite layers ranges from 8 to 22. High-resolution TEM images demonstrate the interlayer distance in the UCCL of approximately 0.33 nm, which corresponds to the crystallographic planes (002) of hexagonal graphite. The obtained UCCL can be used as a reinforcing component in the CC matrix to create materials with increased hardness and wear resistance.
This paper presents a method for synthesizing quasicrystalline carbon-reinforced AlCuFe alloy in the form of onions using a high-energy ball mill. This method allows obtaining composite materials with a uniform distribution of the reinforcing component in the matrix.
Powders of high purity aluminum, copper, and iron, as well as carbon nanotubes (CNTs), were used as starting materials. A mixture of powders with a given ratio of Al:Cu:Fe = 62:25.5:12.5 (at.%) and different CNT contents (0, 1, 3, and 5 wt.%) was subjected to mechanical alloying in a high-energy ball mill in an argon atmosphere. The resulting powders were studied by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy.
X-ray analysis showed that after mechanical alloying, a quasi-crystalline phase of icosahedral type is formed. Increasing the content of CNTs leads to a decrease in the size of crystallites of the quasi-crystalline phase. Microscopic studies revealed the formation of onion-shaped structures consisting of a quasi-crystalline matrix surrounding carbon nanotubes. CNTs act as nucleation centers of the quasi-crystalline phase and contribute to the formation of onion-shaped morphology.
The high-energy ball mill method is an effective way to synthesize carbon-reinforced AlCuFe quasicrystals in the form of onions. By varying the parameters of mechanical alloying and the CNT content, it is possible to control the structure and properties of the resulting composite materials. The results obtained open up prospects for creating new materials with improved mechanical characteristics based on quasicrystals.
Author: C. Patiño-Carachure, J. E. Flores-Chan, A. Flores Gil, G. Rosas
Institute: Faculty of Engineering, Autonomous University del Carmen, Campus III, Avenida Central, 24115, Ciudad del Carmen, Campeche, Mexico, Metallurgy and Materials Research Institute, UMSNH, CP 58000, Morelia, MI, Mexico