Preparation of quasicrystalline particles with uniform size

本课题的目的是尝试建立一种尺寸均匀的准晶颗粒的制备方法。该装置的建立为准晶颗粒作为涂层材料或超精加工用抛光粉的应用提供了可能<-4>。尝试了向下蒸发Al-Mn合金，以便在普通气体蒸发技术的三个生长区中仅形成外部区。然而，由于合金与W、Ta等源材料发生反应，试验失败。其次，通过粒子捕获时间、蒸发温度和气体压力的函数关系，探索了在工作室中制备的所有粒子均为准晶相而无平衡合金相的条件。但是，制备条件的确定比较困难，需要对制备工艺进行进一步的研究。

The purpose of the present project is that an establishmant of the preparation method of quasicrystalline particles with uniform size is tried. The establishment may bring about a possibility of application of quasicrystalline particles as coating materials or polisheng powder for ultra-finishing.A working chamber of stainless steel constructed is 25cm in diameter, 45cm in hight and evacuated down to 5x10^<-4> Pa by using a turbo-molecular pump.For control of the particle size, a downward evaporation of Al-Mn alloy has tried so as to form only outer zone among the three growth zones in ordinary gas evaporation technique. However, the trial has failed due to a reaction of the alloy with the source materials such as W, Ta.Next, the condition of which the all particles prepared in the work chamber are quasicrystalline phase without the equilibrium alloy phase has been searched by the function of capture duration of particles, evaporation temperature and gas pressure. Howerer, it was really difficult to find the condition and is required further investigation on the preparation technique.