Adsorption Behavior of GTMS on AA2024-T3 Aluminum Alloy and the Application on Surface Pretreatment

2020 ◽  
Vol 984 ◽  
pp. 31-42
Author(s):  
Bing Xue ◽  
Xue Mei Zong ◽  
Can Wang ◽  
Hua Yuan Zhang ◽  
Jing Luo

Basing on the study of adsorption behavior of glycidoxypropyl-trimethoxy-silane (GTMS), pretreatment method of AA2024-T3 aluminum alloy for sol-gel films was optimized. The morphology, composition and corrosion protective performance of alloy coated with the films were investigated by using FE-SEM, EDS, AFM and EIS. The results showed that the Al matrix exhibited better ability to adsorb GTMS molecules than the second phase particles, especially at lower concentration of GTMS. Further, the 5% GTMS films cover the whole surface, but the selective adsorption behaviors still exist. It was concluded that less second phase particles and smoother surface were benefit to the sol-gel films on aluminum alloy. Depending on this conclusion, the pretreatment method for sol-gel films was optimized. The optimized surface condition conducted with 50 g•L-1 sodium hydroxide and ultrasound at 60 oC for 30 s was obtained. These samples coated with the sol-gel films revealed good anti-corrosion performance. The coverage degree of the films was up to 97.95 %.

2014 ◽  
Vol 58 ◽  
pp. 535-542 ◽  
Author(s):  
P. Shaterani ◽  
A. Zarei-Hanzaki ◽  
S.M. Fatemi-Varzaneh ◽  
S.B. Hassas-Irani

2013 ◽  
Vol 753 ◽  
pp. 221-224 ◽  
Author(s):  
Krzysztof Sztwiertnia ◽  
Magdalena Bieda ◽  
Anna Korneva

In situ orientation mapping using TEM and calorimetric measurements were carried out to investigate the annealing behavior of cold-rolled 6013 aluminum alloy. The recrystallization of the material can be considered to be a number of processes that correspond to two separate stored energy release peaks. In the temperature range of the peak 1, the deformation zones around the large second-phase particles acted as sites for particle-stimulated nucleation. In the matrix, at the same time, some elongation of grains occurred. The elongated matrix grains appeared because of the reduction of the dislocation density and the annihilation of some low-angle grain boundaries between chains of subgrains lying in layers parallel to the sheet plane. The matrix processes in this temperatures range can be considered forms of continuous recrystallization. The matrix high-angle grain boundaries started to migrate at the temperature range of the peak 2. They moved mostly in the direction normal to the sheet plane. Heating of the sample for an appropriate time at those temperatures resulted in the complete discontinuous recrystallization of the material. The recrystallized microstructure was dominated now by elongated grains, which were a few times thicker than those obtained by annealing at the temperatures of the peak 1.


2011 ◽  
Vol 480-481 ◽  
pp. 433-436
Author(s):  
Mu Meng ◽  
Zhi Min Zhang ◽  
Jian Min Yu ◽  
Xin Kai Li

Aluminum alloy 7A04 compressed at high deformation temperature and large deformation is applied in two different heat treatment (T5 and T6), then microstructure and properties of the alloy after heat treatment are investigated. The mechanical properties are studied by means of the tensile testing and the hardness testing. The microstructure characteristics and the fractorgraphy analysis are respectively investigated with optical microscopy and SEM. The experimental results indicate that after T6 heat treatment, the second-phase particles dispersed in the matrix, which can efficiently improving the strength of the alloy, but reduced the toughness. After T5 heat treatment, the coarse and discontinuous second-phase is distributed along the grain boundary, which can lead to the low strength and high toughness because of the lack of the strengthening phase in the grains. The fracture appearance is intercrystalline fracture after T6 heat treatment, and dimple transgranular fracture after T5 heat treatment.


2010 ◽  
Vol 163 ◽  
pp. 13-18 ◽  
Author(s):  
M. Bieda-Niemiec ◽  
Krzystof Sztwiertnia ◽  
A. Korneva ◽  
Tomasz Czeppe ◽  
R. Orlicki

Orientation mapping in transmission electron microscope was successfully applied to study microstructural changes at the initial stage of recrystallization in the aluminum alloy with a bimodal second-phase particle distribution. The alloy samples were reversibly cold rolled resulting in the formation of laminar structure with zones of localized strain around large second-phase particles. Orientation mapping and in-situ investigations carry information about the processes which are active in the deformation zones during annealing.


2011 ◽  
Vol 399-401 ◽  
pp. 46-49
Author(s):  
Hai Gen Jian ◽  
Xing Er Xie ◽  
Feng Jiang ◽  
Jin Long Li

Observation of fratcure morphology and energy spectrum analysis of fracture toughness specimens of high strength aluminum alloy was carried out on scanning electron microscope (SEM), and the fracture behaviour of this alloy has also been studied. It is revealed that the fracture surface can be divided into 3 regions: precrack region, propagation region and rapid fracture region, the appearance of which is similar to that of cleavage fracture, mixed mode fracture and static fracture, respectively. The fracture of high strength aluminum alloy is primarily influenced by coarsed Fe-rich particles which is relatively brittle, and the major fracture mode of this kind of alloy is toughness fracture casued by coarsed second phase particles.


2013 ◽  
Vol 652-654 ◽  
pp. 2397-2403 ◽  
Author(s):  
Chun Fu Li ◽  
Hong Bin Wang ◽  
Fan Lei Meng ◽  
Hong Yang Zhao

In this study, 7050 aluminum alloy strip was produced using the twin-roll casting technique. Microstructures and properties of the cast-rolling 7050 aluminum alloy were investigated by means of optical microscope (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Vickers hardness test. The results indicate that microstructures of cast-rolling 7050 alloy strip are inhomogeneous on the cross section. From the edge to the center, the size of grain decreases gradually and becomes more homogeneous, showing a transition from dendrite grains to equiaxed grains. There are undissolved second phase particles in grains and at grain boundaries. And the dendrite grains and second phase particles can be reduced by solution treatment, and the hardness of the cast-rolling strip can be improved by aging treatment.


Sign in / Sign up

Export Citation Format

Share Document