Laser cladding of cast aluminum–silicon alloys for improved dry sliding wear resistance

In this study, the dry sliding wear behaviors of SiC particle reinforced AZ91D matrix composites fabricated by stirring casting method were systematically investigated. The SiC particles in as-cast composites exhibited typical necklace-type distribution, which caused the weak interface bonding between SiC particles and matrix in particle-segregated zones. During dry sliding at higher applied loads, SiC particles were easy to debond from the matrix, which accelerated the wear rates of the composites. While at the lower load of 10 N, the presence of SiC particles improved the wear resistance. Moreover, the necklace-type distribution became more evident with the decrease of particle sizes and the increase of SiC volume fractions. Larger particles had better interface bonding with the matrix, which could delay the transition of wear mechanism from oxidation to delamination. Therefore, composites reinforced by larger SiC particles exhibited higher wear resistance. Similarly, owing to more weak interfaces in the composites with high content of SiC particles, more severe delamination occurred and the wear resistance of the composites was impaired.

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Evaluation of Microstructural and Dry Sliding Wear Resistance of Iron-Based SiC-Reinforced Composite Coating by HVOF Process

10.1201/9781003213185-9 ◽

2021 ◽

pp. 229-241

Author(s):

C. Durga Prasad ◽

Akhil Jerri ◽

M. R. Ramesh

Keyword(s):

Wear Resistance ◽

Composite Coating ◽

Sliding Wear ◽

Dry Sliding Wear ◽

Dry Sliding ◽

Reinforced Composite ◽

Hvof Process ◽

Iron Based

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Surface Characterization and Tribological Performance of Anodizing Micro-Textured Aluminum-Silicon Alloys

Materials ◽

10.3390/ma12111862 ◽

2019 ◽

Vol 12 (11) ◽

pp. 1862 ◽

Cited By ~ 2

Author(s):

Luanxia Chen ◽

Zhanqiang Liu ◽

Bing Wang ◽

Qinghua Song ◽

Yi Wan ◽

...

Keyword(s):

Surface Roughness ◽

Friction Coefficient ◽

Sliding Friction ◽

Tribological Performance ◽

Area Ratio ◽

Micro Milling ◽

Dry Sliding ◽

Silicon Alloys ◽

Aluminum Silicon Alloys ◽

Aluminum Silicon

Eutectic aluminum-silicon alloys present high frictional coefficient and a high wear rate due to the low hardness under sliding friction conditions. In this paper, the eutectic aluminum-silicon alloy was textured firstly by micro-milling operations. Then, the micro-textured specimen was subjected to anodizing to fabricate alumina films. The surface topography, surface roughness, and bearing area ratio of micro-textured and anodizing micro-textured specimens were measured and characterized. For the anodizing micro-textured specimens, the surface roughness and superficial hardness increase compared with those for micro-textured ones. Tribological tests indicate that anodizing micro-textured samples present lower friction coefficient of 0.37 than that of flat samples of 0.43 under dry sliding conditions. However, they exhibit higher friction coefficient at 0.16 than that of flat samples of 0.13 under oil-lubricated conditions. The difference between the friction coefficient of anodizing micro-textured and flat samples under dry and oil-lubricated conditions is ascribed to the influence mechanism of surface roughness, bearing area ratio curves, and its relative parameters on the tribological performance of testing samples. The dry sliding friction coefficient has a positive correlation with bearing area ratio curves, while they present negative correlation with bearing area ratio curves under oil-lubricated conditions. The synergy method treated with micro-milling and anodizing provides an effective approach to enhance the dry sliding friction property of eutectic aluminum-silicon alloys.

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Improving the Wear Resistance of Aluminum Fly Ash Composites by Multipass Friction Stir Processing

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.642.55 ◽

2015 ◽

Vol 642 ◽

pp. 55-59 ◽

Cited By ~ 1

Author(s):

Shueiwan Henry Juang ◽

Liang Jing Fan ◽

Hsu Shuo Chang

Keyword(s):

Wear Resistance ◽

Fly Ash ◽

Friction Stir Processing ◽

Sliding Wear ◽

Normal Load ◽

Aluminum Matrix ◽

Dry Sliding Wear ◽

Dry Sliding ◽

Wear Rates ◽

Friction Stir

In this study, the multi-pass friction stir processing (MP-FSP) technique was performed on ADC6 aluminum alloy + 5 wt% fly ash composite (A5FC) castings to increase their surface area. The dry sliding wear behaviors of the ADC6 alloy, A5FCs, and MP-FSPed A5FCs were evaluated. Dry sliding wear tests were performed using a ring-on-washer machine at a constant rotation speed of 100 rpm for 60 min, and the normal load was 10, 20, 30, and 40 N. The results showed that the MP-FSPed A5FCs had the lowest wear rates in the load range from 10 to 40 N, and adhesive wear was the major wear mechanism in these tests. The increased wear resistance was mainly due to grain refinement and elimination of casting defects after subjecting the ash composite to MP-FSP. The microstructure of the MP-FSPed A5FCs reveals that the sizes of the added raw fly ash particles decreased from micro-to nanoscale levels, and the nanoscale fly ash was uniformly dispersed in the aluminum matrix.

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