In this experiment, we tried the production of Al-19.6 wt% Si alloy powders having structures frozen by an extremely rapid cooling velocity, and examined its sintering characteristics by means of dilatometric method.
The results obtained were as follows:
(1) From the relationship between the dendrite arm spacing and its cooling rate, it was assumed that molten drops of Al-19.6 wt%Si alloy was frozen into powders with the cooling rate of about 6×105°C/see, and showed the structure of well defined primary Si, the size of about 1μm.
(2) The Al-19.6 wt%Si alloy powder compacts showed fairly good sintering charactersitics from about 560°C during heating process, and the size of primary Si was of only 5 Fpm even after the sintering at 570°C for 1 hr.