The characteristics of Al

2

Cu phase in casting A319 alloy were analyzed by high-precision three-dimensional X-ray computed tomography

and the effects of different Cu contents and cooling rates on the three-dimensional characteristics of Al

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Cu phase were quantitatively characterized. The results indicate that in the specimens with higher Cu content and lower cooling rate

the variation trend of the three-dimensional characteristics of the Al

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Cu particles is similiar. In terms of the size and amounts

the average and maximum volume of Al

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Cu particles is larger

and the amount is fewer. In terms of morphology

the compactness of particles is increased and the specific surface area is decreased

which means that the structure is more compact with a fewer branches

and the complexity of morphology is reduced. However

comparing with the increase of Cu content

the decrease of cooling rate leads to the significant variation in above-mentioned size

amount and morphology

which is prone to increase the inhomogeneity of Al

2

Cu particle morphology and spatial distribution.