Abstract Creep age forming process (CAF) has been developed for manufacture large aircraft components. Generally, in CAF, the component should experience heating, soaking and cooling stages. In order to acquire high precision of the creep-age formed components, the non-isothermal deformation behavior of Al-Cu-Mg alloy was investigated using the creep ageing, thermal expansion, hot tensile and creep age forming tests. During non-isothermal creep ageing process, both the elastic and thermal deformations grow in the heating stage. However, the elastic deformation drops to a certain degree and then the contraction occurs in the cooling stage. The non-isothermal creep deformation can be divided into six stages, in which the creep rate increases in the heating stage and decreases in the soaking and cooling stages. Under different applied stresses, the creep strain in the heating stage of the non-isothermal creep is about 22.28–26.86% of the total creep strain. Compared with the isothermal creep ageing process, steady-state creep rate of the non-isothermal creep ageing process is reduced. Nevertheless, total creep deformation in the non-isothermal creep ageing process is improved. Thus, the springback of the non-isothermal creep-age formed plate is smaller than that of the isothermal creep-age formed plate. It can be concluded that the creep behavior in non-isothermal conditions, particularly the heating stage, needs to be considered in CAF applications.

中文翻译：

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非等温蠕变时效成形过程中Al-Cu-Mg合金的变形行为

摘要 蠕变时效成形工艺 (CAF) 已被开发用于制造大型飞机部件。通常，在 CAF 中，组件应经历加热、均热和冷却阶段。为了获得高精度的蠕变时效成形部件，采用蠕变时效、热膨胀、热拉伸和蠕变时效成形试验研究了Al-Cu-Mg合金的非等温变形行为。在非等温蠕变老化过程中，弹性和热变形均在加热阶段增长。但是，弹性变形下降到一定程度，然后在冷却阶段发生收缩。非等温蠕变变形可分为六个阶段，其中蠕变速率在加热阶段增加，在均热和冷却阶段降低。在不同的外加应力下，非等温蠕变加热阶段的蠕变应变约为总蠕变应变的 22.28-26.86%。与等温蠕变时效工艺相比，非等温蠕变时效工艺的稳态蠕变速率降低。尽管如此，非等温蠕变时效过程中的总蠕变变形得到改善。因此，非等温蠕变时效成型板的回弹量小于等温蠕变时效成型板的回弹量。可以得出结论，在 CAF 应用中需要考虑非等温条件下的蠕变行为，特别是加热阶段。尽管如此，非等温蠕变时效过程中的总蠕变变形得到改善。因此，非等温蠕变时效成型板的回弹量小于等温蠕变时效成型板的回弹量。可以得出结论，在 CAF 应用中需要考虑非等温条件下的蠕变行为，特别是加热阶段。尽管如此，非等温蠕变时效过程中的总蠕变变形得到改善。因此，非等温蠕变时效成型板的回弹量小于等温蠕变时效成型板的回弹量。可以得出结论，在 CAF 应用中需要考虑非等温条件下的蠕变行为，特别是加热阶段。