Herstellung, Mikrostruktur und Korrosionsverhalten der konventionellen und ultrafeinkörnigen Legierung EN AW‐6082

Wielage, B.; Nickel, Dominik; Lampke, Thomas; Alisch, G.; Podlesak, H.; Darwich, S.; Hockauf, Matthias

doi:10.1002/mawe.200800400

Cited by 5 publications

(5 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In addition, the corrosion resistance of a commercial-purity aluminium alloy was found to be increased after ECAP processing [13,14]. This was linked to the fragmentation of coarse precipitates and their more homogeneous distribution within the matrix, which led to the formation of a more homogeneous and stable natural oxide layer.…”

Section: Introductionmentioning

confidence: 94%

The effect of anodic oxide coating on the fatigue behaviour of AA6082 with an ultrafine‐grained microstructure

Hockauf¹,

Köhler²,

Händel³

et al. 2011

Materialwissenschaft Werkst

Self Cite

View full text Add to dashboard Cite

In this work, the high-cycle fatigue behaviour of the precipitation hardening aluminium wrought alloy AA6082 was investigated for a conventionally-grained and an ultrafine-grained substrate condition, with each a hard and a soft electrolytic anodic oxide (EAO) coating. The investigations were focused on the susceptibility of the coatings to anodising-and fatigueinduced cracking of the coatings and its impact on the fatigue life. For both substrate materials, the fatigue strength of the coated specimens was significantly reduced compared to the uncoated materials. Considering the resistance to crack initiation in the coating, the soft-anodised coatings were found to be superior compared to the hard-anodised ones. Moreover, the coatings on the ultrafine-grained substrate showed an enhanced resistance to anodisinginduced as well as fatigue-induced cracking. However, it is supposed that the lower resistance to crack transition from the coating into the substrate is one of the most important factors which strongly limits the fatigue life of the EAO-coated specimens. This might be the reason why the fatigue strength of the ultrafine-grained substrates is relatively low, despite their higher resistance to crack initiation.Keywords: equal-channel angular pressing (ECAP) / electrolytic anodic oxidation (EAO) / high-cycle fatigue (HCF) / ultrafine-grained / Al-Mg-Si alloy / In dieser Arbeit wird die Ermüdungsfestigkeit der ausscheidungshärtbaren Aluminiumknetlegierung AA6082 an einen normalkörnigen sowie einem ultrafeinkörnigen Zustand mit jeweils einer hart-und einer weichanodisierten Schicht (electrolytic anodic oxiddation, EAO) untersucht. Die Untersuchungen sind darauf ausgerichtet, die Anfälligkeit der Schichten für Rissbildung, sowohl beim Anodisierprozess als auch bei der Ermüdungsbelastung, zu untersuchen und Verbindungen zur Ermüdungsfestigkeit herzustellen. Für beide Substratmaterialien ergibt sich für die beschichteten Zustände eine deutliche Verschlechterung der Ermüdungsfestigkeit. Dabei zeigen sich die hartanodisierten Schichten generell als deutlich rissanfälliger im Vergleich zu den weichanodisierten Schichten. Darüber hinaus kann im Vergleich der Substratzustände festgestellt werden, dass beide Schichttypen auf dem ultrafeinkörnigen Substrat einen erhöhten Widerstand gegen eine anodisierprozessbedingte oder ermüdungsbedingte Anrissbildung besitzen. Die Untersuchungen zeigen jedoch auch, dass vor allem der Widerstand gegen einen Übergang des Risses von der Schicht ins Substrat die Lebensdauer bestimmt. Für die beschichteten ultrafeinkörnigen Substrate könnte hier der Grund für deren relativ niedrige Ermüdungsfestigkeit liegen, die sich trotz des erhöhten Widerstandes gegen Anrissbildung ergibt.Schlüsselwörter: equal-channel angular pressing (ECAP) / elektrolytisch anodische Oxidation (EAO) / ultrafeinkörnig / Ermüdungsfestigkeit / Al-Mg-Si-Legierung /

show abstract

Section: Introductionmentioning

confidence: 94%

The effect of anodic oxide coating on the fatigue behaviour of AA6082 with an ultrafine‐grained microstructure

Hockauf¹,

Köhler²,

Händel³

et al. 2011

Materialwissenschaft Werkst

Self Cite

View full text Add to dashboard Cite

show abstract

“…This difference in grain size could be the reason for the established corrosion behavior. An improved corrosion resistance as a result of finer grain size is also reported in literature [1][2][3][4][5][6][7][8].…”

Section: Resultsmentioning

confidence: 51%

“…Most of them deal with metals and alloys having an ultrafine-grained (UFG) microstructure caused by severe plastic deformation (SPD). In [1] and [2], the effect of a UFG microstructure produced by equal-channel angular pressing (ECAP) in comparison to the conventional coarsegrained material state was studied and a reduced corrosion susceptibility was found due to a reduced precipitation particle size and a more homogeneous distribution of them. In [3], the authors compare pure aluminum with different aluminum alloys.…”

Section: Introductionmentioning

confidence: 99%

Effect of different grain sizes and textures on the corrosion behaviour of aluminum alloy AA6082

Händel

Nickel

Lampke

2011

Materialwissenschaft Werkst

Self Cite

View full text Add to dashboard Cite

Effect of different grain sizes and textures on the corrosion behaviour of aluminum alloy AA6082Einfluss unterschiedlicher Korngrößen und Texturen auf das Korrosionsverhalten der Aluminiumlegierung EN AW-6082The fabrication and processing of aluminum alloys can result in the formation of different grain sizes and textures within the material. The effects of these differences on the corrosion behaviour of the commercially available alloy AA6082 have been investigated. The results of the macro-and microelectrochemical investigations have been compared with each other and with the resulting corrosion appearance. The observed corrosion damage is not always consistent with the measured corrosion and pitting potential. In the finer-grained part, with a strongly preferred orientation of (002) planes parallel to the sample surface, less corrosion damage could be observed than in the coarser-grained part. However, microelectrochemical measurements show a slightly lower pitting potential in the finer-grained part, so that pitting is likely to start earlier in this area.Keywords: aluminum alloy AA6082 / corrosion / microelectrochemistry / grain sizes / texture / Durch Herstellung und Verarbeitung von Aluminiumlegierungen werden Korngröße und Textur beeinflusst. Die Auswirkungen dieser Unterschiede auf das elektrochemische Korrosionsverhalten der kommerziell erhältlichen Legierung EN AW-6082 wurden untersucht. Die Ergebnisse der makro-und mikroelektrochemischen Untersuchungen werden gegenübergestellt und mit den resultierenden Korrosionserscheinungen verglichen. Dabei zeigt sich, dass der beobachtete Korrosionsschaden nicht immer mit den gemessenen Korrosions-bzw. Lochfraßpotenzialen im Einklang steht. Im feinkörnigeren Bereich mit einer starken Vorzugsorientierung der (002)-Netzebenen parallel zur Probenoberfläche finden sich geringere Korrosionsschäden als im grobkörnige-ren Bereich. Allerdings zeigen mikroelektrochemische Messungen ein etwas niedrigeres Lochfraßpotenzial für den feinkörnigeren Bereich, was auf früher einsetzende Lochkorrosion hindeutet.Schlüsselwörter: Aluminiumlegierung EN AW-6082 / Korrosion / Mikroelektrochemie / Korngrößen / Textur /

show abstract

“…Pitting corrosion induced by chloride containing solutions is a significant problem for keeping a stable passive layer and can reduce the material's integrity. Furthermore, UFG aluminium and aluminium alloys show a better corrosion characteristic in comparison to their conventionally grained counterparts . An important problem in corrosion behaviour is the potential difference between the metallographic constituents and their size.…”

Section: Introductionmentioning

confidence: 99%

Electrochemical corrosion studies of ultrafine‐grained aluminium alloy EN AW‐6063

Krüger

Schwarz

Mandel

et al. 2013

Materials & Corrosion

Self Cite

View full text Add to dashboard Cite

The electrochemical corrosion behaviour of ultrafine‐grained EN AW‐6063 processed by equal‐channel angular pressing (ECAP) was investigated in a 0.01 M sodium chloride solution for different numbers of ECAP‐passes. Some of the ECAPed samples were additionally heat treated and show better corrosion resistance in their potentiodynamic polarisation behaviour than the samples without the heat treatment. Investigations of the surface topology indicate more uniform corrosion when compared to the initial state without ECAP and heat treatment. The results of the microscopic observations confirm that the corrosion behaviour is improved by increasing the number of ECAP‐passes and by additional heat treatment.

show abstract

Herstellung, Mikrostruktur und Korrosionsverhalten der konventionellen und ultrafeinkörnigen Legierung EN AW‐6082

Cited by 5 publications

References 15 publications

The effect of anodic oxide coating on the fatigue behaviour of AA6082 with an ultrafine‐grained microstructure

The effect of anodic oxide coating on the fatigue behaviour of AA6082 with an ultrafine‐grained microstructure

Effect of different grain sizes and textures on the corrosion behaviour of aluminum alloy AA6082

Electrochemical corrosion studies of ultrafine‐grained aluminium alloy EN AW‐6063

Contact Info

Product

Resources

About