摘要
通过力学性能测试、20℃电阻率测试及显微组织观察,研究了Si加入量为0.3wt%时对Al⁃1.5Cu⁃0.7Mg合金组织和性能的影响。结果表明,当Si加入量为0.3wt%时,Al⁃1.5Cu⁃0.7Mg合金时效态的强度明显提高,经473~493 K峰时效后,其20℃电阻率为3.638~3.667μΩ·cm,抗拉强度为370~380 MPa。根据马蒂森定律建立了20℃电阻率与时效析出第二相相对体积分数之间的关系式。利用JMA(Johnson⁃Mehl⁃Avrami)方程得出Al⁃1.5Cu⁃0.7Mg和Al⁃1.5Cu⁃0.7Mg⁃0.3Si合金的时效析出激活能分别为135 kJ/mol和204 kJ/mol,由此可判定,Al⁃1.5Cu⁃0.7Mg合金以S″相为主,Al⁃1.5Cu⁃0.7Mg⁃0.3Si合金以S相为主。由JMA方程对其他时效参数下的电阻率进行预测,预测模型的准确性在99%以上。
Effect of 0.3wt%Si addition on the microstructure and mechanical properties of Al⁃1.5Cu⁃0.7Mg alloy was studied by means of mechanical test,resistivity test at 20℃and microstructure observation.The results show that with the 0.3wt%Si addition,the as⁃aged strength of the tested alloy is obviously increased.After peak aging at 473⁃493 K,its 20℃resistivity is 3.638⁃3.667μΩ·cm,and its tensile strength is 370⁃380 MPa,and then the relationship between the 20℃resistivity and the relative volume fraction of the second phase precipitated during aging is established according to Matthiessen rule.The second phase precipitation activation energies in aging of the Al⁃1.5Cu⁃0.7Mg and Al⁃1.5Cu⁃0.7Mg⁃0.3Si alloys obtained by using JMA(Johnson⁃Mehl⁃Avrami)equation are 135 kJ/mol and 204 kJ/mol respectively,according to which to know that the S″phase is dominant in the Al⁃1.5Cu⁃0.7Mg alloy and the S phase is dominant in the Al⁃1.5Cu⁃0.7Mg⁃0.3Si alloy.The resistivity under other aging parameters is also predicted by JMA equation,and the accuracy of the prediction model is all over 99%.
作者
谭鑫禹
刘静静
刘东雨
Tan Xinyu;Liu Jingjing;Liu Dongyu(School of Energy,Power and Mechanical Engineering,North China Electric Power University,Beijing 102206,Chi)
出处
《金属热处理》
CAS
CSCD
北大核心
2024年第2期53-59,共7页
Heat Treatment of Metals
