Plastic Deformation and Ductility of AA7075 and AA6013 at Warm Temperatures Suitable to Retrogression Forming
Plastic Deformation and Ductility of AA7075 and AA6013 at Warm Temperatures Suitable to Retrogression Forming
复制标题
DOI：
10.1007/s11661-021-06360-z
复制
发表时间：
2021-07
期刊：
影响因子：
--
通讯作者：
K. Rader;J. Carter;L. Hector;E. Taleff
中科院分区：
文献类型：
--
作者：
K. Rader;J. Carter;L. Hector;E. Taleff
同时进行回归热处理的温成形工艺（称为回归成形）可以使高强度铝合金实现良好的成形性，并在成形后通过一次再时效热处理恢复其高强度。给出了两种商用铝合金板材AA 7075-T6和AA 6013-T6在回归成形条件下的拉伸数据。AA 7075-T6板材在180 °C至220 °C的温度和3.2 × 10− 3至10− 1 s −1的应变速率下进行测试。AA 6013-T6板材在230 °C至250 °C和3.2 × 10− 3至10− 1 s −1条件下进行测试。这两种材料在这些温度下表现出几乎稳态的流动，并产生适度的应变率敏感性ofm= 0.039。在这些条件下，AA 7075-T6和AA 6013-T6的塑性流动活化能分别为221 kJ/mol和253 kJ/mol。试验数据用于构建流变应力作为温度和应变速率的函数的预测模型。AA 7075-T6在200 °C和高达10− 1 s − 1的应变速率下，如果温度保持在12分钟以下，则具有良好的回归成形潜力。AA 6013-T6在240 °C和高达10− 1 s − 1的应变速率下，如果在温度下的时间保持在7分钟以下，则表现出适度的回归成形潜力。
A warm forming process with a simultaneous retrogression heat treatment, termed retrogression forming, can achieve good formability in high-strength aluminum alloys and recover their high strength through a single reaging heat treatment after forming. Tensile data from two commercial aluminum alloy sheet materials, AA7075-T6 and AA6013-T6, are presented for conditions suitable to retrogression forming. AA7075-T6 sheet was tested at temperatures from 180 °C to 220 °C and strain rates from 3.2 × 10−3to 10−1s−1. AA6013-T6 sheet was tested from 230 °C to 250 °C and 3.2 × 10−3to 10−1s−1. Both materials exhibit nearly steady-state flow at these temperatures and produce a modest strain-rate sensitivity ofm= 0.039. The activation energies for plastic flow under these conditions are 221 kJ/mol for AA7075-T6 and 253 kJ/mol for AA6013-T6. Test data are used to construct predictive models for flow stress as a function of temperature and strain rate. AA7075-T6 demonstrates an excellent potential for retrogression forming at 200 °C and strain rates up to 10−1s−1if time at temperature is held to under 12 minutes. AA6013-T6 exhibits a modest potential for retrogression forming at 240 °C and strain rates up to 10−1s−1if time at temperature is held to under 7 minutes.