The Effects of Thermo-Mechanical Treatment on the Properties of 2519 Aluminum Alloy

2007 ◽  
Vol 546-549 ◽  
pp. 1027-1032
Author(s):  
Gao Yong Lin ◽  
Zhen Feng Zhang ◽  
Qi Quan Lin ◽  
Da Shu Peng

A procedure of thermo-mechanical treatment (TMT) was carried out to 2519 aluminum alloy to improve its properties. The influences of cold deformation ratio, ageing temperature and ageing time of the TMT on the mechanical properties and electrochemical corrosion resistance of this alloy were investigated. The results show that after TMT the tensile strength of 2519 aluminum alloy can be improved obviously but its electrochemical corrosion resistance decreases slightly. The optimum processing parameters of the TMT for 2519 aluminum alloy can be described as: solid solution at 530°Cfor 0.5h, then cold deform with a ratio of 15% followed by aging at 150°C for 10h.

2020 ◽  
Vol 326 ◽  
pp. 05004
Author(s):  
Zhiguo Chen ◽  
Chenghua Lu ◽  
Jing Peng ◽  
Zhengui Yuan

The comprehensive performance of Al-Zn-Mg-Cu alloy can be significantly improved by a proposed novel thermo-mechanical treatment (NTMT). The influence of the NTMT on the properties and microstructure was investigated by tensile test, corrosion resistance test, X-ray diffraction (XRD), and transmission electron microscopy (TEM). Results show that Al-Zn-Mg-Cu alloy treated by the NTMT can obtain an excellent combination of strength and ductility. The highest yield strength and ultimate tensile strength reached 643 MPa and 664 MPa respectively, and the elongation was 9.7%. Meanwhile, electrochemical corrosion resistance and intergranular corrosion resistance in the aluminum alloy can be improved after the NTMT. The mechanism of the excellent combination of strength and ductility is thought to be the synergistic effect of dislocations substructures, texture configuration, and nanoprecipitates. The improvement of intergranular corrosion resistance of the aluminum alloy is caused by changes in the micro-morphology of grain boundary precipitates after the NTMT, which can block anodic dissolution channels along grain boundaries to reduce the rate of anodic dissolution and avoid hydrogen embrittlement.


2016 ◽  
Author(s):  
Hao Wang ◽  
Yihui Huang ◽  
Zhenying Du ◽  
Wenwu Zhang ◽  
Mengxue Bi

Laser shock peening is an innovation technique due to its significant improvement on the corrosion resistance of metallic materials. The study describes the effect of laser shock peening with multiple LSP impacts on the corrosion resistance of 2024 aluminum alloy in NaCl water solution with a mass fraction of 3.5% by using electrochemical technique. The experimental results reveal that LSP significantly reduces the corrosion rate of 2024 aluminum alloy, and as the number of impacts increases the corrosion rate decreases. The study demonstrates that LSP is an effective method to improve the electrochemical corrosion resistance of 2024 aluminum alloy.


Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4965
Author(s):  
Congwei Li ◽  
Jialei Zhu ◽  
Zhihai Cai ◽  
Le Mei ◽  
Xiangdong Jiao ◽  
...  

Combined with the technologies of underwater local dry laser cladding (ULDLC) and underwater local dry laser remelting (ULDLR), a duplex stainless steel (DSS) coating has been made in an underwater environment. The phase composition, microstructure, chemical components and electrochemical corrosion resistance was studied. The results show that after underwater laser remelting, the phase composition of DSS coating remains unchanged and the phase transformation from Widmanstätten austenite + intragranular austenite + (211) ferrite to (110) ferrite occurred. The ULDLR process can improve the corrosion resistance of the underwater local dry laser cladded coating. The corrosion resistance of remelted coating at 3 kW is the best, the corrosion resistance of remelted coating at 1kW and 5kW is similar and the corrosion resistance of (110) ferrite phase is better than grain boundary austenite phase. The ULDLC + ULDLR process can meet the requirements of efficient underwater maintenance, forming quality control and corrosion resistance. It can also be used to repair the surface of S32101 duplex stainless steel in underwater environment.


2020 ◽  
Vol 67 (2) ◽  
pp. 150-157
Author(s):  
Kong Dejun ◽  
Li Jiahong

Purpose The purpose of this paper is to evaluate the salt spray corrosion (SSC) and electrochemical corrosion performances of CrNi, TiAlN/NiCr and CrNi–Al2O3–TiO2 coatings on H13 steel, which improved the corrosion resistance of H13 hot work mold. Design/methodology/approach CrNi, TiAlN/NiCr and CrNi–Al2O3–TiO2 coatings were fabricated on H13 hot work mold steel using a laser cladding and cathodic arc ion plating. The SSC and electrochemical performances of obtained coatings were investigated using a corrosion test chamber and electrochemical workstation, respectively. The corrosion morphologies, microstructure and phases were analyzed using an electron scanning microscope, optical microscope and X-ray diffraction, respectively, and the mechanisms of corrosion resistance were also discussed. Findings The CrNi coating is penetrated by corrosion media, producing the oxide of Fe3O4 on the coating surface; and the TiAlN coating is corroded to enter into the CrNi coating, forming the oxides of TiO and NiO, the mechanism is pitting corrosion, whereas the CrNi–Al2O3–TiO2 coating is not penetrated, with no oxides, showing the highest SSC resistance among the three kinds of coatings. The corrosion potential of CrNi coating, TiAlN/CrNi and CrNi–Al2O3–TiO2 coatings was –0.444, –0.481 and –0.334 V, respectively, and the corresponding polarization resistances were 3,074, 2,425 and 86,648 cm2, respectively. The electrochemical corrosion resistance of CrNi–Al2O3–TiO2 coating is the highest, which is enhanced by the additions of Al2O3 and TiO2. Originality/value The CrNi, TiAlN/CrNi and CrNi–Al2O3–TiO2 coatings on H13 hot work mold were firstly evaluated by the SSC and electrochemical performances.


Metals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 224 ◽  
Author(s):  
Tamara Aleksandrov Fabijanić ◽  
Marin Kurtela ◽  
Irbas Škrinjarić ◽  
Johannes Pötschke ◽  
Markus Mayer

The advantages of nanostructured cemented carbides are a uniform, homogenous microstructure and superior, high uniform mechanical properties, which makes them the best choice for wear-resistant applications. Wear-resistant applications in the chemical and petroleum industry, besides mechanical properties, require corrosion resistance of the parts. Co as a binder is not an optimal solution due to selective dissolution in an acidic environment. Thus, the development of cemented carbides with alternative binders to increase the corrosion resistance but still retaining mechanical properties is of common interest. Starting mixtures with WC powder, grain growth inhibitors GGIs; VC and Cr3C2, and an identical binder amount of 11-wt.% were prepared. GGIs were added to retain the size of the starting WC powder in the sintered samples. The parameters of the powder metallurgy process were adapted, and samples have been successfully consolidated. A very fine homogeneous microstructure with relatively uniform grain-size distribution and without microstructural defects in the form of carbide agglomerates and abnormal grain growth was achieved for both Ni-bonded and Co-bonded samples. Achieved mechanical properties, Vickers hardness, and Palmqvist toughness, of Ni-bonded near-nanostructured cemented carbides are slightly lower but still comparable to Co-bonded nanostructured cemented carbides. Two samples of each grade were researched by different electrochemical direct current corrosion techniques. The open circuit potential Ecorr, the linear polarisation resistance (LPR), the Tafel extrapolation method, and the electrochemical impedance spectroscopy (EIS) at room temperature in the solution of 3.5% NaCl. From the carried research, it was found that chemical composition of the binder significantly influenced the electrochemical corrosion resistance. Better corrosion resistance was observed for Ni-bonded samples compared to Co-bonded samples. The corrosion rate of Ni-bonded cemented carbides is approximately four times lower compared to Co-bonded cemented carbides.


Sign in / Sign up

Export Citation Format

Share Document