Effect of friction surfacing parameters on microstructure and mechanical properties of solid-solutionized AA2024 aluminium alloy cladded on AA1050

The present study aims to investigate the effect of friction surfacing parameters on the mechanical properties and microstructure of coating fabricated by a solid solutionized consumable rod on the AA1050 substrate. In this regard, the AA2024 aluminum alloy consumable rod was friction surfaced on AA1050 substrate by the rotational speed of 600-1000 rpm, axial feeding rate of 75-200 mm/min, and traverse speed of 100-150 mm/min. The microstructure and mechanical characteristics of coatings showed that increasing the rotational speed, traverse speed, and axial feeding rate results in increasing the unbonded zone extent at the interface of the coating and the substrate. The solid solutionized consumable rod leads to a coating with less width and height in all friction surfacing parameters compared to coatings fabricated by a rod with T3 heat treatment conditions. The average grain size of the coating decreases with decreasing axial feeding rate, increasing traverse speed, and decreasing rotational speed. Although friction surfacing can significantly weaken the fiber texture of consumable rods, the texture intensity in the coatings is slightly changed by changing the friction surfacing parameters. The competitive effect of precipitation hardening and grain refinement mechanisms has a decisive role in the hardness and strength of the coating; however, the influence of the strengthening mechanism through precipitates is much stronger than other mechanisms. Coating fabricated by rotational speed, traverse speed, and axial feeding rate of 1000 rpm, 100 mm/min, and 75 mm/min, respectively, results in the maximum hardness (122.21 VHN0.1) and shear strength (195.65 MPa).