Article
Nanoscience & Nanotechnology
Yan Zou, Xiaodong Wu, Songbai Tang, Yichang Wang, Kai Zhao, Lingfei Cao
Summary: Pre-ageing and pre-stretching can significantly affect the precipitation during artificial ageing in Al-Zn-Mg-Cu alloys, leading to improvements in strength and hardness. The effects of pre-ageing are consistent in enhancing strength, while pre-stretching shows varying effects depending on the alloy composition. Both pre-ageing and pre-stretching are effective ways to reduce PFZ width by promoting precipitation near the grain boundary.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Muhammad Abubaker Khan, Chenhao Xu, Muhammad Hamza, Mohamed A. Afifi, Naeem Akhtar Qaisrani, Huibin Sun, Bin Wang, Waheed Qamar Khan, Ghulam Yasin, Wei -Bing Liao
Summary: An investigation was conducted to study the influence of peak-ageing and double ageing treatments on the precipitation along different grain boundary orientations of an extruded Al-Zn-Mg-Cu alloy. The results showed that the type of grain boundary precipitates varied depending on the grain boundary orientation and treatment. The study provides new insights into engineering the grain boundary precipitates to achieve desired precipitate types and corresponding mechanical properties.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Chemistry, Physical
Haitao Jiang, Hui Xing, Zihan Xu, Bing Yang, Enquan Liang, Jiao Zhang, Baode Sun
Summary: In this study, the effects of high Zn content and adding Sc and Zr on aging precipitation behavior and mechanical properties in Al-Zn-Mg-Cu alloys are investigated using advanced electron microscopy techniques, XRD, tensile tests and quantitative calculations. The results show that the Al-9.2Zn-2.2Mg-2.3Cu-0.2Sc-0.15Zr alloy has higher peak strength and improved mechanical properties compared to other alloys. The addition of Sc and Zr leads to the formation of nano-structured Al3(Sc,Zr) precipitates and the precipitation of eta' phases, resulting in enhanced strength and plasticity.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Zhaorui Zhang, Yue Li, Yaohong Liu, Hongxiang Li, Di Zhang, Jishan Zhang
Summary: Improving the strength is crucial for the development of high-performance Al-Mg-Zn(-Cu) crossover alloys. A new ultra-high strength Al-5.64 Mg-5.43Zn-0.51Cu (wt.%) crossover alloy was designed using CALPHAD assisted design, with yield strength, tensile strength, and elongation of 570.7 ± 2.7 MPa, 628.0 ± 9.6 MPa, and 9.5 ± 0.2%, respectively. Compared to existing crossover alloys and the 7075-T6 alloy, this alloy exhibits the highest yield strength (70.7 MPa higher than the second) with an acceptable elongation. The high-solute supersaturation of Mg, Zn, and Cu elements promotes the precipitation of the high-density T-type phases, hindering dislocation movement and increasing the strength of the alloy. The developed ultra-high strength Al-Mg-Zn(-Cu) crossover alloy is expected to be a favorable material option for lightweight transportation industries.
Article
Chemistry, Physical
V. A. Esin, L. Briez, M. Sennour, A. Koster, E. Gratiot, J. Crepin
Summary: The precipitation map of Al-Cu-Mg alloy (AA2024-T3) was obtained by combining differential scanning calorimetry analysis and high-resolution transmission electron microscopy observations, revealing the appearance of equilibrium S-Al2CuMg phase at 85 degrees C after 1000 h of ageing. Hardness values showed that the maximum hardness was located at the boundary between S-phase + GPB zones and S-phase regions for all studied temperatures.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Engineering, Multidisciplinary
Zheng QiuJu, Jiang HongXiang, He Jie, Zhang LiLi, Zhao JiuZhou
Summary: The study found that micro-alloying La addition does not change the overall precipitation sequence and atomic structure of precipitates during artificial aging of Al-Mg-Si alloys. However, the higher La-vacancy binding energy and strong La-Si and La-Mg interactions can decrease the solubility of Si and Mg in the Al matrix, reducing the beta'' precipitation activation energy and improving the strength and electrical conductivity of Al-Mg-Si alloys simultaneously.
SCIENCE CHINA-TECHNOLOGICAL SCIENCES
(2021)
Article
Materials Science, Multidisciplinary
Jiwu Huang, Chenglong Xu, Shichao Liu, Fuqing Jiang
Summary: This paper investigates a novel Al-Zn-Mg-Cu-Mn-Sc-Zr alloy with excellent quenching sensitivity and a quench-hardening depth of more than 150 mm. Different quenching rates affect the hardness of the alloy, and after artificial aging, various precipitates are observed on the grain boundaries and different phase interfaces.
Article
Materials Science, Multidisciplinary
Xingpu Zhang, Xiaotong Deng, Haofei Zhou, Jiangwei Wang
Summary: The precipitation behavior of a 7075 Al alloy during isochronal heat treatments was studied using various techniques. The influence of heating rate and ending temperature on the formation of precipitates was analyzed.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Physical
Chunhua Wei, Zhixin Lei, Sijie Du, Rongyou Chen, Yutang Yin, Chenglin Niu, Zhengbing Xu
Summary: The microstructure of Al-Zn-Mg-Cu alloy was influenced by multiaxial forging (MAF) and aging treatment. MAF resulted in dislocation multiplication and grain refinement, accelerating the nucleation and growth of precipitated phases. Precipitates on grain boundaries were coarse and discontinuously distributed due to the presence of dislocations and grain boundaries. The MAF and aging alloy exhibited higher hardness and strength, with values of 202 HV and 606 MPa, respectively, while maintaining good ductility at 16.2%.
Article
Materials Science, Multidisciplinary
Yong Li, Yin Wang, Bing Lu, Wei Yu, Haiyao Wang, Guangming Xu, Zhaodong Wang
Summary: Al-Zn-Mg-Cu alloys were prepared using water-cooled copper casting and characterized by various microstructural analysis techniques. The study demonstrated that increased Cu content enhanced solid solution strengthening and precipitation strengthening, while higher Zn/Mg ratio decreased precipitation strengthening and resulted in decreased strength but increased plasticity of the alloy.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Nanoscience & Nanotechnology
Sang-Hwa Lee, Jae-Gil Jung, Sung-Il Baik, David N. Seidman, Min-Seok Kim, Young-Kook Lee, Kwangjun Euh
Summary: The research revealed that the formation and evolution of GPI and GPII zones during natural aging had a significant impact on the mechanical properties of the Al-7.6Zn-2.7Mg-2.0Cu-0.1Zr-0.07Ti alloy. The Zn/Mg atomic ratio, mean radius, number density, and volume fraction of the GP zones also played crucial roles in influencing the mechanical properties of the alloy.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Ruixuan Li, Zheng Ren, Yuan Wu, Zhanbing He, Peter K. Liaw, Jingli Ren, Yong Zhang
Summary: Designing a quinary alloy based on the concept of high-entropy alloys enables the achievement of high strength and deformability at high zinc content levels in Al-based alloys. The precipitation transformation plays a key role in contributing to the desired mechanical properties.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Yingxin Geng, Qi Song, Zhaorui Zhang, Yanlin Pan, Hongxiang Li, Yuan Wu, Huihui Zhu, Di Zhang, Jishan Zhang, Linzhong Zhuang
Summary: This study quantifies the early stage precipitation strengthening behavior of a newly developed Al-Mg-Zn alloy by particle size distribution. The results show that the rapid strengthening response strongly depends on the number density and constitution of Guinier-Preston zones, and is increased by the addition of Cu. The strength of the alloy is quantified by evaluating different types of precipitates.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Wenyuan Gong, Ruixuan Li, Mengjing Xie, Yuan Wu, Jishan Zhang
Summary: In this study, the effect of Mg content and precipitation behaviors in Al-Mg-Si-Cu-Zn alloys on alloy performance was reported. By increasing the alloying degree, the low strength of 6xxx aluminum alloys was improved and the strength of the alloys exceeded that of traditional 6xxx aluminum alloys. The alloy exhibited excellent strengthening effects at high temperatures and is expected to have significant effects in practical applications.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Materials Science, Multidisciplinary
Yan Zou, Xiaodong Wu, Songbai Tang, Qianqian Zhu, Hui Song, Mingxing Guo, Lingfei Cao
Summary: The study investigated the effects of Zn/Mg ratios on the microstructure and mechanical properties of Al-Zn-Mg-Cu alloys aged at 150 degrees C. It was found that an increase in Zn/Mg ratios significantly accelerates the aging process, with the co-existence of T' phase and eta' phase beneficial to the high strength of the alloys.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)