抄録
The shrinkage of aluminium, Al-Si, Al-Cu and Al-Mg alloys of which one side was cooled was studied by continuous measurement of temperature and the change of length from 850°C to room temperature on the top of specimens. The results obtained were as follows : 1) The shrinkage-temperature curves from the liquid state to the room temperature were continuously obtained on aluminium and its alloys. 2) The amount of the shrinkage was increased with the increasing of temperature gradient of specimens on the cooling at liquid and the solidification. 3) The amount of shrinkage was depended on the shape of specimens in the process of solidification. 4) There was no relation between the amount of shrinkage and the load holding from the liquid state to room temperature on specimens (weight 1.20-14.9 g/cm2). 5) The amount of shrinkage was decreased with the increasing the alloying elements of specimens. 6) The amount of total shrinkage of aluminium alloys from 850°C to room temperature was much depended on the amount of shrinkage on the occasion of solidification. 7) Two stages of shrinkage were found in the proceeding of solidification of Al-Si and Al-Cu alloys. This phenomenon was due to the proceeding the region of the partial solidification in the proceeding of solidification of alloys, so above two stages were not found on aluminium and eutectic alloys. 8) The expansion which was due to the formation of blow holes in the region of partial solidification at the proceeding of solidification was found on Al-Mg alloys.
