Author:R. Nicula, M. Stir, F. Turquier, E. Burkel
Institute: Institute of Physics, University of Rostock, August-Bebel-Str. 55, 18055 Rostock, Germany
We report the in situ synthesis of single-phase bulk quasicrystals using a spark plasma sintering (FAST/SPS) method starting from ball-milled nanopowders. Our sintering process involves partial melting of the starting alloy powder followed by rapid cooling of the resulting part. The formation of an Al-rich phase at grain boundaries is kinetically inhibited. We demonstrate that the FAST/SPS method can create bulk nano-quasicrystalline Al–Cu–Fe solids with high chemical homogeneity and uniform microstructure.
Quasicrystals (QCS) are aperiodic solids with unique properties that are of interest for technology. The complexity of synthesizing single-phase Al–Cu–Fe quasicrystals by slow casting is due to narrow compositional regions. This study considers the possibility of using spark plasma sintering to form bulk nanoquasicrystal materials. The FAST/SPS method can significantly reduce the sintering time, which helps to retain small grain sizes. We investigate the effect of pulsed current on the formation of QC phases during rapid heating of mechanically alloyed Al–Cu–Fe powders using the FAST/SPS method.
Single-phase bulk Al–Cu–Fe quasicrystals produced by field sintering are a unique state of matter with remarkable properties that combine characteristics of both crystalline and amorphous materials. Characterized by high structural integrity, these quasicrystals exhibit unusual symmetries that are not found in traditional crystals. Their complex electronic structure predetermines many physical and chemical properties, such as high hardness, low friction coefficient, and exceptional corrosion resistance.
The field sintering method used to obtain them allows for significant control over the microstructure and phase transformations during synthesis. Temperature and pressure parameters of sintering play a decisive role in shaping the final properties of the obtained samples. Experiments show that such quasicrystals can open up new horizons in the field of materials science, providing new solutions for structural materials and nanotechnology.
Research conducted on Al–Cu–Fe quasicrystals opens the way to the creation of new functional materials with unique mechanical and physical characteristics that will facilitate innovation in various fields of science and technology.