高应变率拉伸下纯铝中氦泡长大的动力学研究

 分析了高应变率加载下纯铝中氦泡长大的动力学过程，给出了含内压氦泡长大的动力学方程，并且分别研究了氦泡内压、基体材料惯性、粘性、表面张力以及基体环境温度对初始半径为1 nm氦泡长大的影响。研究结果表明：（1）初始内压可以促使氦泡快速长大，当氦泡直径超过1 μm时，内压对氦泡长大的影响可以忽略不计。（2）表面张力在氦泡整个长大过程中的影响都很小。（3）材料惯性对氦泡长大起抑制作用，并且随着氦泡半径的增长，抑制效应越来越明显。（4）在所有因素中，温度对氦泡长大的影响最为明显，温度升高，材料的粘性降低，氦泡的内压增加，促使氦泡加速长大。

Dynamic Analysis of Helium Bubble Growth in the Pure Alunder High Strain-Rate Loading

Based on the dynamic process of helium bubble growth under high strain-rate, the dynamic equation of helium bubble growth has been presented. The effects of internal pressure of helium bubble, inertia, viscosity, surface tension of base material and environment temperature on helium bubble with 1 nm radius have been considered respectively. Results indicate that: (1) At high strain-rate loading, the original internal pressure may help to accelerate the growth of the helium bubble. When the radius of helium bubble is larger than 1 μm, the internal pressure is too small and it may be omitted. (2) The effect of surface tension is very weak in the whole process of helium bubble growth. (3) The growth of helium bubble may be restrained by the inertia. And this effect will be more obvious with the growth of diameter. (4) While all the above effects are important, the effect of temperature needs to be particularly emphasized. With the temperature rising, the viscosity will decrease and the internal pressure will increase, the growth of helium bubble will be accelerated.