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Enhancement of mechanical properties and wear of AA5083/316 stainless steel surface-composite developed through multi-pass friction stir processing (MPFSP)

Yang Yiran, Paidar Moslem, Mehrez Sadok, Ojo Olatunji Oladimeji

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 1

art. no. e13, 2023

EN

In this investigation, the AA5083/316 stainless steel (ss) surface composite was generated by the friction stir processing (FSP) with the aim of improving the mechanical properties, the corrosion and tribological performances of the composite. The FSP process was conducted at different tool pass numbers (1-P, 2-P, and 4-P) and a constant tool rotational (900 rpm) and travel (85 mm/min) speeds. To analyze the microstructure of the samples, optical (OM) and scanning electron microscopes (SEM) were employed to characterize the scattering of the 316 stainless steel (ss) particles within the AA5083 matrix. It was found that multi-pass FSP resulted in substantial grain refinement from 7.02 to 5.89 μm and better scattering of the reinforcement in the AA5083 Al matrix. Results also indicated that the mechanical and wear properties of the composite layers were enhanced by increasing the pass number from 1-pass to 4-pass, which can be credited to the formation of finer 316 stainless steel (ss) particles appropriately dispersed in the Al substrate. Furthermore, the results depicted that the corrosion resistance of the samples is enhanced with the increase of pass number.

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Tribological behavior of AA7050-ZrSiO4 composites synthesized by stir casting technique

Sakthivelu S., Meignanamoorthy M., Ravichandran M., Sethusundaram P. P.

Mechanics and Mechanical Engineering

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2019

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Vol. 23, nr 1

198--201

EN

This research made an attempt to synthesize aluminum metal matrix composites through stir casting technique. The matrix material chosen in this study was AA7050 and the reinforcement material was ZrSiO4. The composites AA7050, AA7050-10%ZrSiO4, and AA7050-15%ZrSiO4 were used. The wear behavior of the aluminium matrix composites was investigated by using pin-on-disc tribometer. The advanced material has substantial development in tribological behavior when the reinforcement percentage is increased. From the experimental results, it was confirmed that sliding distance of 1200 m, applied load of 3 N and sliding speed of 2 m/s result in minimum wear loss and coefficient of friction, while adding 10%ZrSiO4 to the AA7050.

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Influence of FSP process modification on selected properties of Al-Si-Cu/SiCp composite surface layer

Stawiarz Michał, Kurtyka Paweł, Rylko Natalia, Gluzman Simon

Composites Theory and Practice

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2019

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R. 19, nr 4

161--168

EN

The paper presents the results of mechanical and tribological tests conducted on the surface of Al-Si-Cu/SiCp composite reinforced with SiC particles and modified by friction stir processing (FSP) with different parameters. Changes in the distribution of the reinforcement particles on the modified surface of the composite were calculated and analyzed using a new analytical RVE theory with Eisenstein-Rayleigh-Mityushev sums (ERM-sum) (see the definitions below), and PointSel software. The Vickers hardness test with a 1 N load and the ball-on-disc method were used to test the material properties. A high degree of homogenization of the tested material was observed as a result of its modification, as evidenced by an approximately 4-fold reduction in the size of representative volume element (RVE) cells. The size of the RVE cell decreased almost four times for the material after modification, which indicates the high level of homogenization of the tested material. Moreover, we observed a reduction by order of magnitude of the anisotropy coefficient of the distribution of the reinforcing phase particles after the modification process. A 30% increase in the Vickers microhardness of the representative areas was obtained for the modified composites. After the FSP modification process the friction coefficient increases by 40%, and almost 25% decrease in the specific wear rate is observed. Both effects are attributed to the achieved homogenization of particle distribution and reduction of particle size up to 38%.

PL

Przedstawiono wyniki badań właściwości mechanicznych i tribologicznych powierzchni kompozytów Al-Si-Cu/SiCp modyfikowanych metodą FSP z różnymi parametrami. Zmianę rozkładu cząstek wzmacniających na powierzchni kompozytu zbadano z wykorzystaniem nowej analitycznej teorii RVE oraz ERM-sums i programu PointSel. Testy twardości przeprowadzono metodą Vickersa przy obciążeniu 1 N, a testy ścieralności wykonano metodą ball-on-disc. Po procesie modyfikacji stwierdzono wysoki stopień homogenizacji, który cechował się około czterokrotnym zmniejszeniem wielkości komórki RVEc oraz spadkiem o rząd wielkości wartości współczynnika anizotropii rozkładu cząstek fazy wzmacniającej. Zaobserwowano około 30% wzrost mikrotwardości Vickersa w modyfikowanym kompozycie. Po procesie modyfikacji FSP stwierdzono również 40% wzrost wartości współczynnika tarcia oraz blisko 25% spadek wartości wskaźnika zużycia, wynikający z ujednorodnienia struktury i redukcji wielkości cząstek SiC, dochodzącej do 38%.

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Experimental method of tribological modelling of different coatings of stainless steel

Djilali K. A., Serrier M.

Mechanics and Mechanical Engineering

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2018

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Vol. 22, nr 4

1273--1285

EN

Fretting wear is a unique form of material degradation caused by small amplitude oscillatory relative motion of two surfaces in contact. Fretting wear is typically encountered at relative displacements of less than 300 m and occurs in either a gross slip regime [1] (where there is slip displacement across the whole contact), or a partial slip regime (where there are parts of the contact where no slip displacement occurs). Fretting wear is experienced within a wide range of industrial sectors, [2] including aero engine couplings, locomotive axles and nuclear fuel casings [3]. Under higher loads and smaller displacement amplitudes, the contact will be within the partial slip regime, often resulting in fretting fatigue where the dominant damage mode is a reduction in fatigue life [4]. Friction is a very common phenomenon in daily life and industry, which is governed by the processes occurring in the thin surfaces layers of bodies in moving contact. The simple and fruitful idea used in studies of friction is that there are two main non-interacting components of friction, namely, adhesion and deformation [5, 6].