Aging effects on the wear behaviour of PM SiC reinforced aluminium alloys

To improve the performance and effectiveness of cost, constructing lightweight structure is the important factor for automobile, naval and aerospace industries. AA5052 and AA6101-T6 aluminium alloys are widely applied in transport industries, due to their lightweight and high strength and hence, joining of these two are unavoidable. Friction stir welding is an unconventional welding method, which is developed for constructing lightweight structures. This work describes the detailed study of friction stir welded dissimilar AA5052 and AA6101-T6 alloys. AA5052 and AA6101-T6 plates are welded with rotation rates of 765–1400 rpm and offset distances at advancing side of 0–2 mm. For this purpose, four levels of welding parameters based on Taguchi L16 orthogonal array are chosen. To determine the optimum combinational levels and identify the effect of above-mentioned parameters on tensile and wear properties, Signal to Noise ratio and ANOVA respectively are used. From the results, it is observed that the combination of 1 mm offset distance at advancing side and 1400 rpm rotating speed produces better tensile and wear properties, which is due to high heat generation, sufficient flow of materials and balanced precipitation and strain hardening effects. On the other hand, the combination of 2 mm tool offset at advancing side and 765 rpm rotational rate exhibits poor properties, which is associated with low heat input, defects formation, precipitate coarsening and lesser strain hardening effects.

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Analysis of Tribological Properties in Disks of AA-5754 and AA-5083 Aluminium Alloys Previously Processed by Equal Channel Angular Pressing and Isothermally Forged

Metals ◽

10.3390/met10070938 ◽

2020 ◽

Vol 10 (7) ◽

pp. 938

Author(s):

Carmelo J. Luis Pérez ◽

Rodrigo Luri Irigoyen ◽

Ignacio Puertas Arbizu ◽

Daniel Salcedo Pérez ◽

Javier León Iriarte ◽

...

Keyword(s):

Equal Channel Angular Pressing ◽

Aluminium Alloys ◽

Mean Value ◽

Wear Behaviour ◽

Volume Loss ◽

Angular Pressing ◽

Ring Configuration ◽

Ecap Process ◽

Initial States ◽

Accumulated Deformation

In the present study, the wear behaviour of two aluminium alloys (AA-5754 and AA-5083) is analysed where these have been previously processed by severe plastic deformation (SPD) with equal channel angular pressing (ECAP). In order to achieve the objectives of this study, several disks made of these alloys are manufactured by isothermal forging from different initial states. The microstructures of the initial materials analysed in this study have different accumulated deformation levels. In order to compare the properties of the nanostructured materials with those which have not been ECAP-processed, several disks with a height of 6 mm and a diameter of 35 mm are manufactured from both aluminium alloys (that is, AA-5754 and AA-5083) isothermally forged at temperatures of 150 and 200 °C, respectively. These thus-manufactured disks are tested under a load of 0.6 kN, which is equivalent to a stress mean value of 18 MPa, and at a rotational speed of 200 rpm. In order to determine the wear values, the disks are weighed at the beginning, at 10,000 revolutions, at 50,000 revolutions and at 100,000 revolutions, and then the volume-loss values are calculated. This study was carried out using specific equipment, which may be considered to have a block-on-ring configuration, developed for testing in-service wear behaviour of mechanical components. From this, the wear coefficients for the two materials at different initial states are obtained. In addition, a comparison is made between the behaviour of the previously ECAP-processed aluminium alloys and those that are non-ECAP-processed. A methodology is proposed to determine wear coefficients for the aluminium alloys under consideration, which may be used to predict the wear behaviour. It is demonstrated that AA-5754 and AA-5083 aluminium alloys improve wear behaviour after the ECAP process compared to that obtained in non-ECAP-processed materials.

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Tool wear behaviour and the influence of wear-resistant coatings during refill friction stir spot welding of aluminium alloys

Welding in the World ◽

10.1007/s40194-020-01021-y ◽

2020 ◽

Author(s):

Dennis Lauterbach ◽

Daniel Keil ◽

Alexander Harms ◽

Christoph Leupold ◽

Klaus Dilger

Keyword(s):

Tool Wear ◽

Aluminium Alloys ◽

Spot Welding ◽

Friction Stir Spot Welding ◽

Wear Behaviour ◽

Wear Resistant ◽

Wear Resistant Coatings ◽

Friction Stir

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Influence of lubrication, tool steel composition, and topography on the high temperature tribological behaviour of aluminium

Friction ◽

10.1007/s40544-020-0371-6 ◽

2020 ◽

Vol 9 (1) ◽

pp. 155-168

Author(s):

Justine Decrozant-Triquenaux ◽

Leonardo Pelcastre ◽

Braham Prakash ◽

Jens Hardell

Keyword(s):

High Temperature ◽

Tool Steel ◽

Aluminium Alloys ◽

Friction And Wear ◽

Weight Ratio ◽

High Strength ◽

Wear Behaviour ◽

Tribological Behaviour ◽

Material Transfer ◽

The Stability

Abstract The use of high strength aluminium alloys, such as 6XXX and 7XXX series, is continuously increasing for automotive applications in view of their good strength-to-weight ratio. Their formability at room temperature is limited and they are thus often formed at high temperatures to enable production of complex geometries. Critical challenges during hot forming of aluminium are the occurrence of severe adhesion and material transfer onto the forming tools. This negatively affects the tool life and the quality of the produced parts. In general, the main mechanisms involved in the occurrence of material transfer of aluminium alloys at high temperature are still not clearly understood. Therefore, this study is focussed on understanding of the friction and wear behaviour during interaction of Al6016 alloy and three different tool steels in as-received and polished state. The tribotests were carried out under dry and lubricated conditions, with two distinct lubricants, using a reciprocating friction and wear tester. The worn surfaces were analysed using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results showed a high dependence of friction and wear behaviour on the tool steel roughness as well as on the stability of the lubricant films. Tribolayers were found to develop in the contact zone and their capacity to improve the tribological behaviour is seen to be drastically impacted by the surface roughness of the tool steel. When the tribolayers failed, severe adhesion took place and led to high and unstable friction as well as material transfer to the tool steel.

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Comparative wear behaviour of aluminium alloys

Journal of Materials Science Letters ◽

10.1007/bf01742242 ◽

1986 ◽

Vol 5 (11) ◽

pp. 1186-1188 ◽

Cited By ~ 6

Author(s):

K. Narasimha Rao ◽

J. A. Sekhar

Keyword(s):

Aluminium Alloys ◽

Wear Behaviour

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Erosive wear behaviour of aluminium alloys: a comparison between slurry and dry erosion

Materials Research Express ◽

10.1088/2053-1591/ab1aee ◽

2019 ◽

Vol 6 (8) ◽

pp. 086503 ◽

Cited By ~ 1

Author(s):

Vinayaka R Kiragi ◽

Amar Patnaik

Keyword(s):

Aluminium Alloys ◽

Erosive Wear ◽

Wear Behaviour

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Effect of Pre-Straining and Natural Aging on the Hardening Response during Artificial Aging of EN AW 6082 and Lead Free EN AW 6023 Aluminium Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.952.82 ◽

2019 ◽

Vol 952 ◽

pp. 82-91

Author(s):

Martin Fujda ◽

Miloš Matvija ◽

Peter Horňak

Keyword(s):

Aluminium Alloys ◽

Artificial Aging ◽

Solution Treatment ◽

Natural Aging ◽

Age Hardening ◽

Aging Effects ◽

Β Phase ◽

Transmission Electron ◽

Negative Effect ◽

Microscopy Characterization

In order to study the pre-straining and natural aging effects on the age-hardening response of EN AW 6082 and EN AW 6023 aluminium alloys during artificial aging at 170°C, the pre-straining by 5% was performed immediately after solution treatment of alloys at 550°C and subsequent quenching. The age-hardening response during artificial aging applied after various natural aging time (from 0.1 to 5 000 hours) was investigated using Vickers microhardness measurements and transmission electron microscopy characterization. It was found that pre-straining of quenched alloys state caused a dislocation density increasing in solid solution, which resulted in an immediate microhardness increase of alloys. During the subsequent natural aging of EN AW 6082 alloy, its microhardness increased right after alloy quenching and pre-straining, but only to the values obtained for the unstrained alloy state. On the contrary, the hardness of pre-straining EN AW 6023 alloy that is alloyed by Sn did not increase either after 10 hours of natural aging. This phenomenon is attributed to the effect of Sn on suppression of the strengthening clusters formation. The hardness of alloys increased greatly during artificial aging after pre-straining and natural aging due to accelerating the formation of coherent β″-phase particles. The negative effect of natural aging on the maximum age-hardening response obtained during alloys artificial aging had been observed for most of the pre-strained and naturally aged alloys states, with exception of EN AW 6023 alloy states that were pre-strained and shortly naturally aged (up to 100 hours).

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