scholarly journals Influence of Extrusion Temperature on the Corrosion Behavior in Sodium Chloride Solution of Solid State Recycled Aluminum Alloy 6061 Chips

Crystals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 353
Author(s):  
Nabeel H. Alharthi ◽  
El-Sayed M. Sherif ◽  
Mohamed A. Taha ◽  
Adel T. Abbas ◽  
Hany S. Abdo ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Aluminum Alloy ◽  
Elevated Temperatures ◽  
Electrochemical Impedance ◽  
Corrosion Current ◽  
Extrusion Temperature ◽  
Sem Images ◽  
Current Time ◽  
Aluminum Alloy 6061 ◽  
Alloy 6061

In the present work, aluminum alloy 6061 (AA6061) device chips were subjected to cold compaction monitored by an extrusion procedure at an extrusion ratio of 5:2 and elevated temperatures of 350, 425, and 500 °C, respectively. The influence of changing temperature on the corrosion of the extruded alloys after 1 h and 24 h in 3.5% NaCl solutions was studied. The polarization (cyclic potentiodynamic polarization, CPP) results indicated that the corrosion decreases with the increase of extrusion temperature of AA6061 from 350 to 500 °C. Impedance (electrochemical impedance spectroscopy, EIS) experiments provided a remarkable increase in the corrosion resistance with rising the extrusion temperature. Potentiostatic current-time (PCT) curves indicated that the current initially increased then decreased for all alloys after 1 h measurements. Prolonging the exposure time to 24 h was observed to decrease the rate of corrosion for all AA6061 alloys as proved by CPP and EIS data. This effect was found to increase the pitting corrosion as indicated by the measured PCT curves and by the scanning electron microscopy (SEM) images for the surface of the alloys. The surface layers formed on AA6061 alloys were mostly composed of aluminum oxide as presented by the spectra of the energy dispersive X-ray analyzer (EDX). All results indicated that the increase of the temperature of extrusion increased the corrosion resistance via decreasing the corrosion current and corrosion rate, and that this effect was found remarkably increased when the immersion time increased from 1 to 24 h exposure to the chloride test solution.

scholarly journals Enhanced Corrosion Resistance of Recycled Aluminum Alloy 6061 Chips Using Hot Extrusion Followed by ECAP

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Mohamed A. Taha ◽  
Adel T. Abbas ◽  
Faycal Benyahia ◽  
Hamad F. Alharbi ◽  
B. Guitián ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Aluminum Alloy ◽  
Material Properties ◽  
Saline Solution ◽  
Electrochemical Impedance ◽  
Hot Extrusion ◽  
Ecap Process ◽  
The Cost ◽  
Alloy 6061 ◽  
Resultant Material

The oxidation of aluminum machining chips retards the successful recycling through the conventional remelting route. A promising approach to overthrow this problem is the utilization of solid state recycling in converting aluminum machining chips directly into semifinished products to eliminate the cost of the remelting process and reduce CO2 emissions. Therefore, in recent work, chips of aluminum alloy (AA6061) were recycled by compaction and then extrusion conducted at 500°C, followed by equal channel pressing (ECAP) to study the resultant material properties and its microstructure. Moreover, the present investigation explores the influence of ECAP after hot extrusion on the corrosive behaviour of the recycled samples in saline solution (NaCl) by electrochemical impedance spectroscopy (EIS) and linear polarization (LP). The results demonstrated a remarkable enhancement of the recycled chips’ properties subjected to hot extrusion followed by the ECAP process. Furthermore, the successive ECAP passes leads to increased film thickness and decreased corrosion rate.

Study on Preparation and the Characteristics of Environment-Friendly Ce-Ti-Mn Conversion Coating on Aluminum Alloy 6061

2014 ◽  
Vol 881-883 ◽  
pp. 1385-1390
Author(s):  
Xian Fang Yang ◽  
Tian Quan Liang ◽  
Wei Wei ◽  
Dong Hui Deng ◽  
Guang Qiao Xu ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Aluminum Alloy ◽  
Room Temperature ◽  
Ph Value ◽  
Conversion Coating ◽  
Environment Friendly ◽  
Aluminum Alloy 6061 ◽  
Coating Characteristics ◽  
Surface Morphologies ◽  
Alloy 6061

Preparation and the characteristics of environment-friendly Ce-Ti-Mn conversion coating on aluminum alloy 6061 were investigated by XRD, FESEM, EDS, TEM and AFM in this paper. It is indicated that coating characteristics such as the surface morphologies, microstructure and corrosion resistance, are greatly influenced by the formation technology at room temperature. The constituents and their concentration, and pH value of the conversion solution have an important role on the feature of Ce-Ti-Mn conversion film, which will significantly influence on the continuity, compactness and the crystalline structure of particles of the film. The concentrations of the main salt K2TiF6and oxidizer KMnO4have significant effect on the characteristics of the conversion coating. The Ce-Ti-Mn film grows in a lamellar way, composing of oxide and/ or hydroxide phases of Ce, Ti and Mn, some of which are amorphous. The formation mechanism of the Ce-Ti-Mn conversion coating is discussed in detail.

scholarly journals Enhancing a Junior Level Materials Lab with SEM Iimages

2011 ◽  
Author(s):  
Aezeden Mohamed ◽  
Ron Britton
Keyword(s):  
Aluminum Alloy ◽  
Fracture Surface ◽  
Alloy Steel ◽  
Team Work ◽  
Scale Level ◽  
Sem Images ◽  
Aluminum Alloy 6061 ◽  
Self Confidence ◽  
Macro Scale ◽  
Alloy 6061

Lab courses can enhance a student's communicationskills, provide opportunities to practice team work, and raise self-confidence early in their university experience, as well as impart valuable technical knowledge. Students ran impact Charpy tests on alloy steel 1045, and aluminum alloy 6061 as a function of temperature, and then analyzed and investigated by unaided eye the fracture surface in the two alloys at the macro-scale level. In this paper, micro-scale level investigation by the scanning electron microscopy (SEM) images introduced for the first time in this context to enhanced junior level materials lab. Keywords: Students: SEM images: alloy steel 1045; aluminum alloy 6061; fracture surface

scholarly journals Cr3C2-NiCr Coating for the Protection of API Steel Corrosion in Concentrated Sodium Chloride Solution

Crystals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 249
Author(s):  
El-Sayed M. Sherif ◽  
Magdy M. El Rayes ◽  
Hany S. Abdo
Keyword(s):  
Corrosion Resistance ◽  
Sodium Chloride ◽  
Corrosion Rate ◽  
Electrochemical Impedance ◽  
Pipeline Steel ◽  
Protective Layer ◽  
Steel Corrosion ◽  
Corrosion Current ◽  
Cyclic Polarization ◽  
Current Time

In the present work, a layer of 75%Cr3C2−25%NiCr with thickness of 260 ± 15 µm was coated onto the API-2H pipeline steel surface using high-velocity oxy-fuel deposition. The effect of 75%Cr3C2−25%NiCr coating on the corrosion of the API steel after 1 h, 24 h, and 48 h exposure in 4.0% sodium chloride solutions is reported. The corrosion tests were performed using potentiodynamic cyclic polarization, electrochemical impedance spectroscopy, and chronoamperometric current–time techniques along with scanning electron microscopy and energy-dispersive X-ray analyses. The curves of polarization indicated that the presence of the coating increases the corrosion resistance of the steel through decreasing its corrosion current and corrosion rate. Impedance data showed that all resistances recorded higher values for the coated API steel. Chronoamperometric current–time measurements confirmed that the coated API steel has lower absolute current values and thus lower corrosion rate. All results proved that the presence of 75%Cr3C2−25%NiCr coating enhances the corrosion resistance of the API steel via the formation of a protective layer of Cr and Ni oxides, which could lead to decreasing the corrosion rate.

scholarly journals Effect of extrusion temperature on the surface roughness of solid state recycled aluminum alloy 6061 chips during turning operation

2017 ◽  
Vol 9 (10) ◽  
pp. 168781401773415 ◽  
Author(s):  
Adham Ezzat Ragab ◽  
Mohamed Adel Taha ◽  
Adel Taha Abbas ◽  
Essam Ali Al Bahkali ◽  
Ehab Adel El-Danaf ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Aluminum Alloy ◽  
Solid State ◽  
Extrusion Temperature ◽  
Turning Operation ◽  
Aluminum Alloy 6061 ◽  
Alloy 6061

Zincating Effect on Corrosion Resistance of Electroless Ni-P Coating on Aluminum Alloy 6061

Fuel Cells ◽  
2017 ◽  
Vol 17 (6) ◽  
pp. 770-777 ◽  
Author(s):  
A. G. González Gutiérrez ◽  
M. A. Pech-Canul ◽  
P. J. Sebastian
Keyword(s):  
Corrosion Resistance ◽  
Aluminum Alloy ◽  
Aluminum Alloy 6061 ◽  
Electroless Ni ◽  
Alloy 6061

KAISER ALUMINUM ALLOY 6061

Alloy Digest ◽  
1999 ◽  
Vol 48 (10) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Shear Strength ◽  
Aluminum Alloy ◽  
Physical Properties ◽  
Surface Treatment ◽  
Tensile Properties ◽  
Heat Treating ◽  
Kaiser Aluminum ◽  
Aluminum Alloy 6061 ◽  
Alloy 6061

Abstract Kaiser Aluminum alloy 6061 has excellent joining characteristics and good acceptance of coatings (anodizing response). It is used in applications where weldability and corrosion resistance are needed. The alloy is typically used in fittings, brake pistons, computer parts, couplings, and valves. This datasheet provides information on composition, physical properties, hardness, tensile properties, and shear strength as well as fatigue. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: AL-360. Producer or source: Tennalum, A Division of Kaiser Aluminum. Originally published March 1999, corrected October 1999.

Investigation on the Corrosion Resistance of PIM 316L Stainless Steel in PEM Fuel Cell Simulated Environment

2010 ◽  
Vol 660-661 ◽  
pp. 209-214 ◽  
Author(s):  
Mara Cristina Lopes de Oliveira ◽  
Isolda Costa ◽  
Renato Altobelli Antunes
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Fuel Cell ◽  
Large Scale ◽  
316L Stainless Steel ◽  
Electrochemical Impedance ◽  
Pem Fuel Cell ◽  
Corrosion Current ◽  
Pem Fuel Cells ◽  
Sem Images

Bipolar plates play main functions in PEM fuel cells, accounting for the most part of the weight and cost of these devices. Powder metallurgy may be an interesting manufacturing process of these components owing to the production of large scale, complex near-net shape parts. However, corrosion processes are a major concern due to the increase of the passive film thickness on the metal surface, lowering the power output of the fuel cell. In this work, the corrosion resistance of PIM AISI 316L stainless steel specimens was evaluated in 1M H2SO4 + 2 ppm HF solution at room temperature during 30 days of immersion. The electrochemical measurements comprised potentiodynamic polarization and electrochemical impedance spectroscopy. The surface morphology of the specimens was observed before and after the corrosion tests through SEM images. The material presented low corrosion current density suggesting that it is suitable to operate in the PEM fuel cell environment.

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