The evolution kinetics of hydrogen porosity during solid solution treatment (SST) of vacuum-cast Al–Cu–Li alloys and the effect of porosity defects on the mechanical properties of the alloys were investigated. It has been found that porosity at 6h SST was dominated by nucleation and its evoluton of fractions has a linear correlation with time, = (0.05 ± 0.06)＋(0.11 ± 0.01) . However, the growth of porosity at 12 h is evidenced by a decrease in the number of pores and an increase in the size of large pores, expanding inter-porosity distance due to Ostwald ripening. Three dimensional quasi- X-ray CT quantification of porosity demonstrate that the hydrogen concentration at the interface in the early stages of the solid solution was not adequate to balance its surface tension and vacancies were created by cross-diffusion, reducing the interficial energy for porosity nucleation. The effects of porosity on the tensile strength satisfies lnσ-lnσ = ln, and those detrimental hydrogen porosities can be predicted by a multi-scale model which take into account hdyrogen diffusion during vacuum solution treatment.

中文翻译：

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固溶处理对 Al-Cu-Li 合金析氢动力学和力学性能的影响

研究了真空铸造Al-Cu-Li合金固溶处理(SST)过程中氢孔隙的演化动力学以及孔隙缺陷对合金力学性能的影响。研究发现，6h SST时的孔隙率以成核为主，其分数演化与时间呈线性相关，=(0.05±0.06)+(0.11±0.01)。然而，12小时时孔隙率的增长表现为孔隙数量的减少和大孔隙尺寸的增加，由于奥斯特瓦尔德熟化导致孔隙间距离扩大。三维准X射线CT孔隙率定量表明，固溶体早期界面处的氢浓度不足以平衡其表面张力，并且通过交叉扩散产生空位，降低了孔隙率的界面能成核。孔隙率对拉伸强度的影响满足lnσ-lnσ = ln，并且可以通过考虑真空固溶处理过程中氢气扩散的多尺度模型来预测那些有害的氢孔隙率。