%0 Journal Article %T 均匀化退火后冷却条件对Al-Cu合金组织性能影响 %A 刘蛟蛟 %A 韩钰 %A 祝志祥 %A 陈保安 %A 张宏宇 %A 李红英 %J 材料科学与工业 %D 2016 %R 10.11951/j.issn.1005-0299.20160408 %X 为优化铝合金均匀化退火后的冷却工艺参数,采用动态电阻法、扫描电镜、透射电镜观察、能谱分析和硬度测试等方法,研究了均匀化处理后的冷却条件对Al-4%Cu合金组织性能的影响.获得的电阻率-温度曲线与材料的脱溶行为有良好的相关性.随着均匀化处理后冷却速率的降低,实验合金在冷却过程中会依次析出平衡相θ、亚稳相θ′和θ″.绘制了实验合金的CCT图,确定的脱溶敏感温度区间为500~300 ℃.选用合适的冷却工艺可以改善合金的组织性能,冷却时间超过1 000 min,合金有较低的硬度和电阻率.当实验合金均匀化后冷却至室温的时间处于19.4~184.1 min时会析出θ″相,导致硬度和电阻率上升,不利于后续的塑性加工,应该尽量避免.</br>In order to optimize the cooling parameters after homogenization, the microstructure and properties evolutions during the cooling processes have been investigated by in-situ electrical resistivity measurements, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectrometer (EDS) and hardness test. The result has shown that the electrical resistivity curves have a good agreement with the precipitation behaviors. There were three types of precipitates in the studied alloy under different cooling conditions. And the precipitation sequence was equilibrium θ phase, metastable θ′ phase and θ″ phase. The hardness-time and resistivity-time curves revealed that choosing a suitable cooling condition could improve the microstructures and performance of the alloy. The optimal cooling time was exceeding 1 000 min, so that the hardness and resistivity of the alloy was located in a low level. However, the cooling should avoid being finished in the 19.4~184.1 min. The precipitation of θ″ phase in this range would lead to the increasing of hardness and resistivity, which was harmful to the subsequent plastic working. %K Al-Cu合金 %K 冷却条件 %K 电阻率 %K 硬度 %K 微观组织< %K /br> %K Al-Cu %K alloy %K cooling %K process %K electrical %K resistivity %K hardness %K microstructure %U http://hit.alljournals.cn/mst_cn/ch/reader/view_abstract.aspx?file_no=20160408&flag=1