摘要
为了研究同步冷却热成形工艺对可热处理铝合金的显微组织演变规律以及强化机制的影响,选用H18态AA2024铝合金板料进行同步冷却热成形及自然时效试验,并进行力学性能测试、光学显微组织观察及TEM分析。结果表明:同步冷却热成形工艺对AA2024铝合金的显微组织影响明显;H18态AA2024铝合金板料经过同步冷却热成形及96 h自然时效后,试样变形区的位错密度增加,并出现细针状的Al_2CuMg(S′)相,使得变形区的屈服强度及抗拉强度分别较冷冲压工艺试样提高4%、12%;此时,AA2024铝合金的强化机制主要是弥散相Al_(20)Cu_2Mn_3(T相)和沉淀相Al_2Cu Mg(S′相)对位错的钉扎作用,以及位错间的相互作用。
Hot forming test with synchronous cooling, metallographic and TEM observation and tensile test were performed to investigate the influence of hot forming with synchronous cooling operations on the microstrueture evolution and strengthening mechanism of AA2024-H18 aluminum alloy. The results show that, the yield strength of hot formed AA2024 sheet with 96 h natural aging is 4%, which is superior to that of traditionally formed sheet, and meanwhile, the tensile strength is increased by 12%. Based on the microstructure observation and analysis, the strengthening is generated by the increase of the dislocation density and precipitation of some fine acicular particles in form of A12CuMg （S″）. The main strengthening mechanism of AA2024 aluminum alloy underwent hot forming with synchronous cooling is the pinning effect of dispersoid phase A120Cu2Mn3 （7） and precipitated phase Al2CuMg （S″） on dislocation as well as the interaction of dislocation.
作者
陈国亮
陈明和
王宁
孙佳伟
CHEN Guo-liang CHEN Ming-he WANG Ning SUN Jia-wei(College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China Department of Mould Technology, Changzhou Institute of Meehatronic Technology, Changzhou 213164, China)
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2017年第7期1337-1343,共7页
The Chinese Journal of Nonferrous Metals
基金
国家自然科学基金资助项目(51175252)~~
关键词
同步冷却热成形
AA2024铝合金
显微组织
强化机制
力学性能
hot forming with synchronous cooling
AA2024 aluminum alloy
microstructure
strengthening mechanism
mechanical behavior
