Tensile Testing and Macrographic Examination of Resistance Spot Welding on Aluminum–Copper–Magnesium Alloy Sheet in Accordance with AWS D17.2

The growing use of aluminum alloys in modern aerospace structures requires reliable and standardized joining methods to ensure structural integrity and weight efficiency.Resistance spot welding (RSW) offers a promising alternative to mechanical fastening and fusion welding due to its high speed, low cost, and suitability for thinsheet materials.This study evaluates the feasibility of RSW on 2024-T42 aluminum sheets with dissimilar thicknesses of 0.6 mm and 0.8 mm in accordance with American Welding Society AWS D17.2.Pre-production specimens were tested using tensile shear and macrographic analyses following ASTM International ASTM E8 and ASTM E340 standards.The average tensile shear load was 318.22 lbf, exceeding the minimum requirement of 235 lbf.Penetration depth (45-55%) and indentation (<0.10 mm) also satisfied the acceptance criteria, while surface resistance prior to welding remained below 50 .These results confirm that RSW of 2024-T42 aluminum sheets with dissimilar thicknesses meets AWS D17.2 requirements and demonstrates its potential as a technically viable and efficient joining process for lightweight aerospace structural components.