2024 Volume 65 Issue 12 Pages 1544-1549
Semi-solid high pressure die casting is known as a process capable of forming high quality products. JIS ADC12 aluminum alloy is widely used for high pressure die casting, but this alloy has a narrow semi-solid temperature range, making it difficult to apply the semi-solid process. In this study, the preparation of ADC12 aluminum alloy slurry by applying mechanical vibration was attempted. Mechanical vibration was applied during the solidification of ADC12 alloy from the liquid to semi-solid state, and the effects of parameters of mechanical vibration and pouring temperature on the morphology of slurry have been investigated.
The application of mechanical vibration transformed the solid phase in the slurry from dendritic shape to fine spherical shape with increasing acceleration amplitude and velocity amplitude. As a result, slurry with solid particles dispersed in the liquid phase could be obtained. Moreover, it was found that high frequencies and displacement amplitudes above a certain value are required to obtain slurry with fine spherical solid particles. Fraction solid of slurry was affected by both the pouring temperature and vibration applied time, increasing with decreasing pouring temperature and increasing vibration time. Consequently, slurry with sufficiently fine spherical particles could be obtained by applying mechanical vibration with the frequency of 50 Hz and acceleration amplitude and velocity amplitude higher than 49.0 m/s2 and 0.19 m/s, respectively. In this way, the fraction solid of ADC12 alloy slurry could be controlled by controlling the pouring temperature and vibrations time.
This Paper was Originally Published in Japanese in J. JFS 95 (2023) 16–22. Figures 8 and 9 were slightly changed.
