Gao Hongwu, Liu Yu, Liu Shikui, et al. Formation and Propagation of Gas Hole in Initial Stages of Foam in Foamed Aluminum. [J]. Special Casting & Nonferrous Alloys (3):136-138(2006)
Gao Hongwu, Liu Yu, Liu Shikui, et al. Formation and Propagation of Gas Hole in Initial Stages of Foam in Foamed Aluminum. [J]. Special Casting & Nonferrous Alloys (3):136-138(2006)DOI:
Formation and Propagation of Gas Hole in Initial Stages of Foam in Foamed Aluminum
aperture configuration and dynamic change of gas hole in the early stages of foamed aluminum were investigated based on preparation of foamed aluminum by a new powder metallurgy method with immersing preformer and heating up rapidly. The results show that foaming process is characterized by micro-propagation to macro-propagation to collapse. The formation mechanism of micro-propagation of crack-gas-hole depends on the stress from H
2
decomposed from TiH
2
characterized by transverse crack in propagation direction and distributed within solid phase. Macro-propagation is attributed to the crack propagation and growth resulting from continuous decomposition of TiH
2
. The new method can reduce the heating time from 10 min to 30
1
50 s
which effectively increase the dynamic mechanism of homogeneous foaming and improve the utilization ratio of TiH