Abstract: In the previous article[9],we mentioned that the cavita-tion phenomenon cannot be described both by the fast expansion and compression of a single gas bubble,because the actual fact is departed far from these kinds of description but close to the equilibrium condition. In this article,we shall go on to tackle the problem,which was discussed in the previous paper[9]. We get the speed and the relaxiation time of approaching to the equilibrium state of a gas bubble,and give out the criterion that the gas bubble may be considered as in equilibrium condition in cavitation phenomenon.

Key words: nanocomposite, thermal elastoplastic, effective thermal expansion, residual interface stress, size-dependent