Effect of double-pass friction stir welding and base materials position on the microstructural and mechanical behaviors of the dissimilar aluminum welded joints of AA6061 and AA2017

Abstract

Abstract Friction stir welding (FSW) is a method of joining solid materials, where the parent metal’s melting temperature is below the point of amalgamation. FSW is a successful method for combining various ferrous and non-ferrous matrix materials. Many researchers’ studies suggested that FSW is suitable for both soft and high melting-point materials by changing the conditional attributes. A defect-free dissimilar weld joint of the alloys AA2017 and AA6061 was fabricated for the current investigation, and the effect of multi-pass friction stir welding (MPFSW) on the development of mechanical and different microstructural behaviors has been investigated. Welding conditions were a constant 1600 rpm weld tool rotational speed, a transverse speed is 32 mm min−1, and a tilt angle of 0°. As a consequence of the pinning effect, the results showed that increasing the number of welding passes in FSW from single to double improved the particle dispersion, which in turn improved the tensile strength, and micro-hardness of the FSWed joint. The primary objectives of this study investigate the strength that was improved because of the rise in the number of passes as well as the effective bonding of the materials’ weld interface, which gives tailor-welded blanks (TWBs) a considerably stronger joint. The findings revealed that the TWB joints’ metallurgical and mechanical properties are extremely varied from single-pass to double-pass, and the position of the base materials can significantly affect the joint properties that are produced.