В работе исследована структура квазикристаллических сплавов Al 65 Co 20 Cu 15 и Al 72 Co 18 Ni 10 , а также композиционных материалов на их основе, полученных методом печной пропитки. Использованы методы металлографического, рентгеноструктурного, электронно-микроскопического и микрорентгеноспектрального анализов. В сплаве Al 65 Co 20 Cu 15 квазикристаллическая декагональная фаза сосуществует с кристаллическими фазами Al 4 (Co, Cu) 3 и Al 3 (Cu, Co) 2 , а в сплаве Al 72 Co 18 Ni 10-с фазами Al 9 (Co 1−х Ni х) 2 и Al 9 (Ni 1−х Co х) 2. Содержание квазикристаллической фазы в сплавах колеблется в пределах 60-65% об. С помощью оригинальной методики автоматизированного структурного анализа построены кривые распределения коэффициентов поглощения света, использованные для расчёта энтропии фаз. В ходе пропитки латунной связкой марки Л62 гранул наполнителей, изготовленных из сплавов Al 65 Co 20 Cu 15 или Al 72 Co 18 Ni 10 , расплавленная связка растворяет кристаллические фазы наполнителя, проникая до центра гранул. При этом квазикристаллическая фаза наполнителей растворяется с гораздо меньшей скоростью. В структуре композиционного материала, упрочнённого сплавомнаполнителем Al 65 Co 20 Cu 15 , содержание квазикристаллической фазы на 15% об. превышает содержание этой фазы в композиционном материале с

The heat capacity of decagonal quasicrystals of the Al–Co–Cu or Al–Co–Ni alloys was calculated at the temperatures of 600, 700, and 900 K in this work. The expression for the heat capacity of the quasicrystals was obtained based on the Debye model. For the quasicrystals, the linear “excessive” heat capacity is observed in the range of temperatures between 400 to 600 К which means the deviation from the 3R Dulong-Petit value. The heat capacity at a temperature of 900 К is about 28.4 J/mol К which is higher than the Dulong-Petit value (~ 25 J/mol К). The “excessive” heat capacity relates to the peculiarities in the decagonal quasicrystal anisotropy. These crystals are quasiperiodic in the x and y directions, and periodic in the z direction. As a result, there is a difference in the dispersive laws in the different directions. The Debye temperature values have essential influence on the temperature dependencies of the heat capacity of the decagonal quasicrystals. Thus, the higher the Debye temperature and the larger “excessive” heat capacity, the more stable are considered the quasicrystals exposed to the temperature effects.

The paper deals with the calculations of heat capacity of quasicrystalline decagonal Al69Co21Ni10 and icosahedral Al63Cu25Fe12 quasicrystalline phases of Al–Co–Ni and Al–Cu–Fe alloys, respectively. According to the Gruneisen law, heat capacity is an energy characteristic, which reflects the phases’ resistance to failure. For calculations of the heat capacity, structure of quasicrystalline phases is considered in the model representation of anisotropic crystals. As a result, it is found that the heat capacity of quasicrystalline phases at high temperatures is the excessive one, i.e. it exceeds the Dulong-Petit value. Therefore, quasicrystalline phases at high temperatures are more stable, than the crystalline phase. For the decagonal quasicrystalline phase, heat capacity is more than 3R in the temperature range of ~480–1500 К, and for the icosahedral quasicrystalline phase – in the temperature range of ~380–1120 К. It follows that decagonal phases remain stable at high temperatures at which the icosahedral phases are destroyed.

The structural and phase composition of dissolution-and-diffusion interfacial zones at the particle-matrix interfaces of the composites reinforced with W–C particles infiltrated by a molten iron-base binder has been investigated. The peculiarities in the filler’s phases dissolution during infiltration have been explained within the framework of computed model allowing the estimation of an average atom oscillation frequency of the investigated phases.

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