Zn含量对Al-xZn-1.5Mg-1.0Cu合金淬火敏感性的影响  

Effect of Zn content on quenching sensitivity of Al-xZn-1.5Mg-1.0Cu alloy

作　　者：曹丽婷 张梦晗 马志民[3] 刘胜胆[1,2,4] CAO Li-ting;ZHANG Meng-han;MA Zhi-min;LIU Sheng-dan(School of Materials Science and Engineering,Central South University,Changsha 410083,China;National Key Laboratory of Light and High Strength Structural Materials,Central South University,Changsha 410083,China;Department of Vehicle Engineering,Baotou Vocational&Technical College,Baotou 014030,China;Key Laboratory of Non-Ferrous Metal Materials Science and Engineering,Ministry of Education,Central South University,Changsha 410083,China)

机构地区：[1]中南大学材料科学与工程学院,长沙410083 [2]中南大学轻质高强结构材料国家重点实验室,长沙410083 [3]包头职业技术学院车辆工程系,包头014030 [4]中南大学有色金属材料科学与工程教育部重点实验室,长沙410083

出　　处：《中国有色金属学报》2023年第5期1458-1468,共11页The Chinese Journal of Nonferrous Metals

基　　金：国家重点研发计划资助项目(2016YFB0300901)。

摘　　要：通过浸入式末端淬火与室温拉伸实验,结合相图和时间-温度-转化率(TTT)曲线、差示扫描量热分析及扫描电镜、透射电镜等手段,研究了Zn含量(6.00%~9.08%,质量分数)对Al-xZn-1.5Mg-1.0Cu合金淬火敏感性的影响。结果表明:当淬火速率从200℃/s减小至70℃/s时,Zn含量为8.10%的合金(8Zn alloy)的淬火敏感性最高,Zn含量为6.00%的合金(6Zn alloy)其次,Zn含量分别为7.09%和9.08%的合金(7Zn alloy,9Zn alloy)的淬火敏感性相当且最低;当淬火速率进一步降低时,Zn含量为9.08%的合金(9Zn alloy)的淬火敏感性快速提高;当淬火速率低于约32℃/s时,随着Zn含量从6.00%增加到7.09%,淬火敏感性基本保持不变;然后随着Zn含量从8.10%增加到9.08%,合金的淬火敏感性迅速增加。结合电导率和淬火诱导相面积分数的结果,从淬火诱导相的析出驱动力和形核位置及数量差异的角度,对Zn含量影响淬火敏感性的机理进行了分析讨论。The effect of Zn content(6.00%-9.08%,mass fraction) on quenching sensitivity of Al-Zn-Mg-Cu alloy was investigated using immersion end-quenching technique,room temperature tensile test,calculation of phase diagram and TTT curves,differential scanning calorimetry measurements,scanning electron microscope and transmission electron microscopy.The results show that,in the quenching rate range from 200 ℃/s to 70 ℃/s,the quenching sensitivity is the highest for 8Zn alloy,intermediate for 6Zn alloy,the lowest for 7Zn alloy and 9Zn alloy;with the further decrease of quenching rate,the quenching sensitivity of 9Zn alloy increases rapidly;when the quenching rate is below about 32 ℃/s,the quenching sensitivity remains basically unchanged with the increase of Zn content from 6.00% to 7.09% and then increases rapidly for 8.10% and 9.08% alloy.Combined with the results of conductivity and quenching-induced phase area fraction,the mechanism of Zn content affecting quenching sensitivity was discussed in terms of the difference of driving force and nucleation sites for precipitation of quenching-induced phase.

关 键 词：AL-ZN-MG-CU合金 浸入式末端淬火 Zn含量 强度 淬火敏感性 

分 类 号：TG146.2[一般工业技术—材料科学与工程]