【摘要】 含特定Cu/Mn比的铝合金能够形成稳定的二十面体准晶相(I-Al₆₅Cu₂₀Mn₁₅)，但是在常规凝固组织中准晶含量较低且尺寸粗大。本文以Al-Cu-Mn准晶合金为研究对象，研究在准晶I相形成温度区间进行熔体保温和超声振动对I相形貌与尺寸的影响规律。结果表明，随着熔体保温时间的延长，准晶I相尺寸呈先减小后增大的趋势，特别是保温时间为20 min时，准晶颗粒呈细小的花瓣状；对保温20 min后的合金熔体施加600 W功率的超声振动，准晶尺寸发生细化，但继续增大功率会导致I相粗化。更多还原

【Abstract】 Alloys with specific Cu/Mn ratios are capable of forming a stable icosahedral quasicrystal phase(I-Al₆₅Cu₂₀Mn₁₅), but under conventional solidification conditions, it is difficult to form a large number of quasicrystal grainswith coarse sizes. This work focused on the study of Al-Cu-Mn quasicrystal alloy,investigating the quasicrystal formation rules through melt holding and ultrasonic vibration in the temperature range of quasicrystal I-phase.The results indicated that with the extension of the melt holding time, the size of the quasicrystal I-phase showed a trend of first decreasing and then increasing, especially when the melt holding time was 20 min, the quasicrystal particles exhibited a fine petal-like shape. Applying 600 W power ultrasonic vibration to the alloy melt after 20 min of meltholding refined the quasicrystal size, but increasing the power further caused coarsening of the I-phase.更多还原