Surface Treatments for Enhancing the Bonding Strength of Aluminum Alloy Joints

Abstract

Aluminum alloy adhesive bonding joint widely appears in many industrial products. Improving the mechanical performances of aluminum alloy bonding joints has been attracting much effort. To acquire more excellent bonding strength, this paper focused on the effects of different surface treatments, including laser ablation and milling superposed by phosphoric acid anodizing (PAA). The treated surfaces were characterized by roughness and contact angle, and the effects of the geometric parameters of microstructures on wettability, failure mode, and shear strength were examined. The results indicate that those surfaces where the spacing is smaller than the diameter present a hydrophilic property and the corresponding specimens are mainly subject to cohesive failure, and vice versa. Additionally, laser ablation with a properly designed dimple pattern can greatly improve the bonding strength, and the maximum average shear strength of specimens with a thickness of 50 μm reaches 32.82 MPa, which is an increase of 28.15% compared with the original milling specimen. Moreover, fabricating groove or grid patterns on the surfaces and applying PAA treatment can also significantly enhance the bonding strength, reaching up to 36.28 MPa.

Influence of Surface Preparation of Aluminum Alloy AW-5754 and Stainless Steel X5CRNI18-10 on the Properties of Bonded Joints

“…Laser ablation was used by Luo et al and Rechner et al to determine the strength of aluminum joints. Luo et al [ 38 ] used laser ablation for texturing and creating suitable surface patterns, which significantly improved the bonding performance and increased the shear strength by 28.15% compared to the original samples. Rechner et al [ 39 ] demonstrated improved strength and durability after laser ablation and showed how laser treatment improved surface cleaning while altering the oxide layer.…”

Application of Organo-Modified Silica Nanoparticles to Improve the Load-Bearing Capacity of Bonded Joints of Dissimilar Steel Substrates

“…A practical example of combining unequal grades of steel is the B-pillar design, where AHSS and mild steel are combined to achieve a compromise between mechanical performance, light weight, and material cost [1,2]. There is a move towards parts composed of different grades and thicknesses of materials, to joining materials of a different material nature (metals + composites), which requires mastery of different joining techniques [3][4][5][6][7][8][9][10][11]. In joining dissimilar materials, bonding technology holds an important position.…”

“…Table 1. An overview of the different methods of improving adhesive-substrate adhesion [3][4][5]. One of the many methods of improving adhesion is the application of organosilanes [4,[12][13][14][15][16].…”