Abstract: Aluminium alloy LY12CZ sheet without any pre-treatment has been used to study the influence of cavity damage on the mechanical properties of the superplastically-deformed materials room temper- ature. The experimental results show that: (1) the lower the rate of cavitation as the superplastic strain increases, the higher the superplasticity is; (2) the mechanical properties of superplastically- deformed materials at room temperature decrease as the superplastically-deformed strain increases, especially, a noteworthy decrease in elasticity modulus, yield strenth and ultimate strength at room temperature begins to appear as the level of cavitation by area comes up to about 4%, while at the same level the reduction in area drops down a very large quantity. Then, a three-layer back- propagation neural network has been developed to predict the machanichl properties of the superplasti- cally-deformed material.The results acquired from the neural network are very inspiring

Key words: superplasticity, cavity, mechanical property, artificial neural network