Analysis of fracture roughness parameters of S355J2 steel and EN AW-2017A-T4 aluminium alloy

The present work is an effort to study the influence of shot peening on the exfoliation corrosion behavior of aluminium alloy (AA) 5083. Surface textural changes induced by shot peening was characterized using microstructural and X-ray diffraction analysis. The surface roughness parameters were measured to study the benefits of peening induced surface topography. Further, the hardness survey was carried out to assess the severe plastic deformation on the peened layers. As a result, excellent resistance against exfoliation corrosion was achieved in the chloride environment. Shot peening plays major role in enhancing the corrosion resistance of AA 5083. In the absence of exfoliation attack, the unpeened sample surfaces such as ground, milled, and as received conditions end up with a significant pitting attack. The findings of this work will be useful for the aluminium alloy fabrications involved in the marine applications.

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Tribological Properties of (EN AW-AlCu4MgSi(A)) Aluminium Alloy Surface Layer After Ball Burnishing

Proceedings of the 8th International Scientific Conference "BALTTRIB 2015" ◽

10.15544/balttrib.2015.11 ◽

2015 ◽

Author(s):

W. Brostow ◽

S. Cygan ◽

K. Czechowski ◽

J. Kalisz ◽

J. Laszkiewicz-Łukasik ◽

...

Keyword(s):

Surface Layer ◽

Structural Material ◽

Aluminium Alloy ◽

Tribological Properties ◽

High Surface ◽

Favorable Effect ◽

Automotive Applications ◽

Roughness Parameters ◽

Ball Burnishing ◽

Alloy Surface Layer

EN AW-AlCu4MgSi(A) aluminium alloy is widely used as a structural material in aerospace and automotive applications. We have subjected it to grinding, polishing and ball burnishing. We have performed ball-on-disk tribological tests. We have also determined normalized 3D roughness parameters. High surface smoothness turns out to be obtainable. Favorable effect of the ball burnishing on the tribological properties of the alloy are seen. Results will be presented at the Conference.

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Surface Finish Analysis in Single Point Incremental Sheet Forming of Rib-Stiffened 2024-T3 and 7075-T6 Alclad Aluminium Alloy Panels

Materials ◽

10.3390/ma14071640 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1640

Author(s):

Tomasz Trzepieciński ◽

Andrzej Kubit ◽

Andrzej Dzierwa ◽

Bogdan Krasowski ◽

Wojciech Jurczak

Keyword(s):

Surface Roughness ◽

Aluminium Alloy ◽

Process Parameters ◽

Rotational Speed ◽

Single Point ◽

Core Material ◽

Tool Rotational Speed ◽

Roughness Parameters ◽

Step Size ◽

Vertical Step

The article presents the results of the analysis of the interactions between the single point incremental forming (SPIF) process parameters and the main roughness parameters of stiffened ribs fabricated in Alclad aluminium alloy panels. EN AW-7075-T6 and EN AW-2024-T3 Alclad aluminium alloy sheets were used as the research material. Panels with longitudinal ribs were produced with different values of incremental vertical step size and tool rotational speed. Alclad is formed of high-purity aluminium surface layers metallurgically bonded to aluminium alloy core material. The quality of the surface roughness and unbroken Alclad are key problems in SPIF of Alclad sheets destined for aerospace applications. The interactions between the SPIF process parameters and the main roughness parameters of the stiffened ribs were determined. The influence of forming parameters on average roughness Sa and the 10-point peak–valley surface roughness Sz was determined using artificial neural networks. The greater the value of the incremental vertical step size, the more prominent the ridges found in the inner surface of stiffened ribs, especially in the case of both Alclad aluminium alloy sheets. The predictive models of ANNs for the Sa and the Sz were characterised by performance measures with R2 values lying between 0.657 and 0.979. A different character of change in surface roughness was found for sheets covered with and not covered with a soft layer of technically pure aluminium. In the case of Alclad sheets, increasing the value of the incremental vertical step size increases the value of the surface roughness parameters Sa and Sz. In the case of the sheets not covered by Alclad, reduction of the tool rotational speed increases the Sz parameter and decreases the Sa parameter. An obvious increase in the Sz parameter was observed with an increase in the incremental vertical step size.

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Surface Roughness after Milling of the Al/CFRP Stacks with a Diamond Tool

Materials ◽

10.3390/ma14226835 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6835

Author(s):

Elżbieta Doluk ◽

Anna Rudawska ◽

Józef Kuczmaszewski ◽

Izabela Miturska-Barańska

Keyword(s):

Surface Roughness ◽

Aluminium Alloy ◽

Surface Topography ◽

Feed Rate ◽

Metal Layer ◽

Composite Layer ◽

Periodic Pattern ◽

Roughness Parameters ◽

Surface Roughness Parameters ◽

Carbon Fibre Reinforced Polymer

This study presents the results of research on the surface quality of hybrid sandwich structures after milling with a diamond blade tool. It identifies the effects of feed and machining strategy on the roughness and topography of the surface. It provides an analysis of Ra and Rz surface roughness parameters as well as Sp, Sz, and Sv surface topography parameters. The processed object was a two-layer sandwich structure consisting of aluminium alloy 2024 and CFRP (carbon fibre-reinforced polymer) composite. The minimum values of the Ra and Rz surface roughness parameters were obtained on the aluminium alloy surface, whereas the maximum values were obtained on the CFRP surface. The same was true for the 3D surface roughness parameters—the lowest values of Sp, Sz, and Sv parameters were obtained on the surface of the metal layer, while the highest values were obtained on the surface of the composite layer (the maximum value of the Sp parameter was an exception). A surface topography analysis has revealed a targeted and periodic pattern of micro-irregularities for the vast majority of the samples considered. The statistical analysis shows that the surface roughness of the aluminium alloy was only affected by the feed rate. For the CFRP, the feed rate and the interaction of milling strategy and feed rate (Sfz) had a statistically significant effect. The obtained results provide a basis for designing such sandwich element processing technology, for which differences in roughness and topography parameters for the component materials are lowest.

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