Quasicrystal is a solid between crystalline and amorphous. Quasicrystals have a long-range ordered atomic arrangement similar to crystals, but do not possess the translational symmetry of crystals, so they can have macro symmetry that crystals do not allow. Quasicrystals are characterized by low surface energy, low friction factor, wear resistance, excellent dispersion, high hardness, high temperature plasticity, high thermal resistance, corrosion resistance and high resistance. At present, the application of quasicrystals lies in composite materials, surface coatings, bulk quasicrystal preparation, hydrogen storage materials, optical materials, etc.
Figure 1. Quasicrystal diffraction pattern
Due to its good physical and chemical properties, diverse preparation methods and great application value, quasicrystals play an important role in surface coating materials, composite materials and other fields.
Figure 2. Quasicrystals are used as non-stick coating materials
According to different criteria, quasicrystals can be classified in many ways. There are currently four main categories: the number of rotational symmetry, alloy components, thermodynamic stability, and quasi-periodic dimension. According to the different times of rotational symmetry, quasicrystals can be divided into five quasicrystals, eight quasicrystals, ten quasicrystals and twelve quasicrystals. According to different alloy components, quasicrystals can be divided into aluminum reference crystal, magnesium reference crystal, zinc reference crystal, zirconium reference crystal, titanium reference crystal, gallium reference crystal, cadmium reference crystal and palladium reference crystal. According to different thermodynamic stability, quasicrystals can be divided into metastable quasicrystals and stable quasicrystals. According to the different quasi-periodic dimensions, quasi-crystals can be divided into one-dimensional quasi-crystals, two-dimensional quasi-crystals and three-dimensional quasi-crystals. Among them, classification according to the period dimension is the most commonly used classification method for quasicrystals.
Commonly used methods for quasicrystals preparation include rapid condensation method, physical and chemical method, mechanical alloying method, meteorological deposition method, electron beam surface rapid melting method, electrodeposition and evaporation condensation method, etc.