The influence of thickness of Ni-P layers produced on AW-7075 aluminum alloy on their adhesion and mechanical properties

The article presents the results of mechanical tests of Ni-P layers deposited by the chemical reduction method on the AW-7075 aluminum alloy. The effect of layer thickness on hardness and microhardness of Vickers, which was determined by the DSI method, and their adhesion to the substrate by scratch method were investigated. The morphology was obtained using light microscopy and the topography of the examined layers using a contact profilometer. Different thicknesses were used to determine their effect on adhesion of the leyers to AW-7075 alloy. The results allowed to state that Ni-P layers of higher thickness are characterized by higher hardness and Young's modulus values than thinner Ni-P layers, and also show better adhesion to the AW-7075 alloy.

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Tribological Properties of Ni-P/Si3N4 Nanocomposite Layers Deposited by Chemical Reduction Method on Aluminum Alloy AW-7075

Materials ◽

10.3390/ma13245797 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5797

Author(s):

Kazimierz Czapczyk

Keyword(s):

Aluminum Alloy ◽

Abrasive Wear ◽

Reduction Method ◽

Chemical Reduction ◽

Contact Method ◽

7075 Aluminum Alloy ◽

Chemical Reduction Method ◽

Phase Layer ◽

Dispersion Phase ◽

7075 Alloy

The article presents the results of tribological tests of Ni-P/Si3N4 nanocomposite and Ni-P nickel layers deposited on the AW-7075 aluminum alloy by chemical reduction method, and the AW-7075 alloy without coating. Nanocomposite layers were produced using Si3N4 siliconnitride in the form of a polydisperse powder whose particle sizes ranged from 20 to 25 nm. The influence of the content of the dispersion phase layer material on the abrasive wear, which was determined as the “ball on disc” method, was analyzed. Surface topography was examined by the contact method using a profilometer. The purpose of introducing Si3N4 particles into the Ni-P layer was to increase the wear resistance of AW-7075 aluminum alloy parts with an embedded nanocomposite coating. Based on the obtained test results, it was found that the Ni-P/Si3N4 layers are more resistant to wear than the Ni-P layers and the AW-7075 alloy layers, and are a good barrier against abrasive wear at various loads and environmental conditions.

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Effect of Heat Treatment on Mechanical Properties of ECAPed 7075 Aluminum Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.829.62 ◽

2013 ◽

Vol 829 ◽

pp. 62-66 ◽

Cited By ~ 2

Author(s):

Alireza Fallahi ◽

Hossein Hosseini-Toudeshky ◽

Seyed Mahmoud Ghalehbandi

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Thermal Stability ◽

Aluminum Alloy ◽

Solution Treatment ◽

7075 Aluminum Alloy ◽

Ecap Processing ◽

Good Thermal Stability ◽

7075 Alloy

It is the objective of this study to investigate the effect of ECAP processing and heat treatment on the mechanical properties of the UFG 7075 alloy. Also the effect of post ECAP heat treatment is investigated. The alloy is processed by ECAP after annealing as well as solution treatment to produce an UFG structure. Furthermore mechanical properties and their variations during annealing and aging are investigated. The hardness of the pre-ECAP annealed and the pre-ECAP solutionised 7075 aluminum alloy has increased significantly compared with that of the CG sample. Also hardness of ECAPed specimen has not experienced significant changes in post-ECAP heat treatment and indicated that the alloy had approximately good thermal stability.

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Microstructure Control and Mechanical Properties of 7075 Aluminum Alloy by Means of Multi-Pass Friction Stir Processing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.409.281 ◽

2011 ◽

Vol 409 ◽

pp. 281-286

Author(s):

Yutaka Matsuda ◽

Goroh Itoh ◽

Yoshinobu Motohashi

Keyword(s):

Mechanical Properties ◽

Aluminum Alloy ◽

Friction Stir Processing ◽

Microstructural Characterization ◽

Tensile Tests ◽

7075 Aluminum Alloy ◽

Tensile Direction ◽

Friction Stir ◽

Electron Microscopies ◽

7075 Alloy

Friction stir processing (FSP) is a method for controlling the microstructure that has been proposed by applying friction stir welding, FSW. In this study, microstructure and mechanical properties of a 7075 aluminum alloy subjected to multi-pass FSP, MP-FSP, are assessed to obtain fundamental knowledge for improving the plasticity of aluminum alloys. The MP-FSP has been applied to 7075 alloy plates with T6 and O tempers, and microstructural characterization has been made by means of optical and scanning electron microscopies together with EDX and EBSD analyses, while mechanical properties were measured by means of micro hardness and tensile tests at room and high temperatures. From microstructural observation, a new zone, PBZ, has been discovered between stir zones, SZs. The PBZ is composed of two types of (fine and coarse) grains, where the coarse grain contains many sub-grains. Hardness in PBZ is intermediate between that in BM and SZ both in T6 and O specimens; hardness generally decreases and increases in T6 and O specimens, respectively, by MP-FSP. In accord to the hardness change, strength at room temperature is decreased by MP-FSP in T6 specimen, and increased in O specimen. Elongation at 773K is increased both in T6 and O specimens because of superplastic deformation. However, local elongation is smaller in PBZ than in SZ, which can be attributed to the microstructural change by the deformation: grain shape remains equiaxed in SZ while it becomes elongated in the tensile direction in PBZ.

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Influence of Tool Geometry on Microstructure and Mechanical Properties of a Friction Stir Welded 7075 Aluminum Alloy

Materials Testing ◽

10.3139/120.110096 ◽

2009 ◽

Vol 51 (11-12) ◽

pp. 788-793 ◽

Cited By ~ 3

Author(s):

Sami Sayer ◽

Qinar Yeni

Keyword(s):

Mechanical Properties ◽

Aluminum Alloy ◽

Tool Geometry ◽

7075 Aluminum Alloy ◽

Friction Stir ◽

Microstructure And Mechanical Properties

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Antimicrobial Activity of Silver Nanoparticles Prepared Under an Ultrasonic Field

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2011.4.3.8 ◽

2011 ◽

Vol 4 (3) ◽

pp. 1491-1496

Author(s):

Umadevi M ◽

Rani T ◽

Balakrishnan T ◽

Ramanibai R

Keyword(s):

Escherichia Coli ◽

Antimicrobial Activity ◽

Silver Nanoparticles ◽

Reduction Method ◽

Therapeutic Potential ◽

Chemical Reduction ◽

Ultrasonic Field ◽

Great Promise ◽

Chemical Reduction Method ◽

E Coli

Nanotechnology has great promise for improving the therapeutic potential of medicinal molecules and related agents. In this study, silver nanoparticles of different sizes were synthesized in an ultrasonic field using the chemical reduction method with sodium borohydride as a reducing agent. The size effect of silver nanoparticles on antimicrobial activity were tested against the microorganisms Staphylococcus aureus (MTCC No. 96), Bacillus subtilis (MTCC No. 441), Streptococcus mutans (MTCC No. 497), Escherichia coli (MTCC No. 739) and Pseudomonas aeruginosa (MTCC No. 1934). The results shows that B. subtilis, and E. coli were more sensitive to silver nanoparticles and its size, indicating the superior antimicrobial efficacy of silver nanoparticles.

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