抄録
The formation of ultrafine intermetallic compound particles in the Al-Cu and Al-Ni systems were examined using a plasma jet method. Pre-mixed elemental powders of Al-Cu and Al-Ni of several tens of pm in diameter were subjected into the plasma jet of Ar-N2 working gas. The ultrafine particles thus formed were examined by X-ray, TEM and EPMA. The main results obtained were as follows; (1) Ultrafine intermetallic compound particles of Al2Cu, AlCu, Al4Cu9 and AlCu3 in the Al-Cu system and Al3Ni, Al3Ni2, AINi and AlNi3 in the Al-Ni system were produced in the present plasma jet method. (2) All the intermetallic compound particles were spherical with the diameter ranging from 1Onm to 100nm. (3) The intermetallic compounds produced were not always with large negative formation energy. Since the cooling rate was relatively fast, the intermetallic compounds which require solid state diffusion at low temperature were not observed. (4) Cu or Ni was richer in the ultrafine particles than that in the source pre-mixed powders. (5) Ultrafine AIN particles were observed when the source pre-mixed powder was Al rich. Such AIN were considered to be produced by the reaction of vapor or liquid Al with the nitrogen in the working gas. AIN was eliminated by using the working gas containing a small amount of H2. (6) The composition of ultrafine particles can be controlled close to that of source powder by reducing the amount of flowing working gas.
