摘要
通过维氏硬度、电导率和室温拉伸、晶间腐蚀等试验,分析比较T6态和回归再时效处理(RRA)态7150铝合金的性能。借助光学显微镜和透射电镜,研究回归时间对RRA态7150铝合金微观组织的影响。结果表明,T6态的7150铝合金强度很高,但抗晶间腐蚀性很差。RRA态的7150合金随回归时间延长,抗晶间腐蚀性能增强,强度先升高后降低。当回归时间为1h时,晶内组织主要析出相为GP区,并伴有细小沉淀相η′,η′相分布较为均匀,约几个nm,晶界处析出相粗大且分布不连续,有明显无沉淀析出带。T6+185℃×1h+T6处理的7150铝合金既具有较高的强度,又具有较好的抗晶间腐蚀性,表现出最佳的综合性能。
The properties of 7150 aluminum alloys in T6 and RRA states were analyzed by means of Vickers hardness test,conductivity test and tensile as well as intergranular corrosion testing.The effects of regression time on the microstructure of 7150 aluminum alloy in RRA state were investigated by optical microscopy(OM)and transmission electron microscopy(TEM).The results show that the 7150 aluminum alloy presents higher strength with poor intergranular corrosion resistance.With the increase of regression time,the intergranular corrosion resistance of the 7150 alloy in RRA state is increased,while the strength is first increased and then decreased.When the regression time is 1 h,the main precipitate in the grain is GP area,accompanied with fine precipitateη′,which is distributed uniformly with the size of several nanometers.The precipitation phase at grain boundary is large and discontinuous with obviously precipitate free zone.The 7150 alloy treated at T6+185℃×1 h+T6 possesses both high strength and good intergranular corrosion resistance,presenting the optimal comprehensive performance.
作者
祝贞凤
梁朋光
孙有政
梁晓宁
Zhu Zhenfeng;Liang Pengguang;Sun Youzheng;Liang Xiaoning(Department of Mechatronics,Yantai Gold College;Shandong Nanshan Aluminum Co.,Ltd.)
出处
《特种铸造及有色合金》
CAS
北大核心
2020年第10期1143-1146,共4页
Special Casting & Nonferrous Alloys
基金
烟台重点研发计划资助项目(2017ZH081)
龙口市科技计划资助项目(2017GG23)
关键词
7150铝合金
回归时间
抗晶间腐蚀性
微观组织
7150 Aluminum Alloy
Regression Time
Intergranular Corrosion Resistance
Microstructure
