TY - JOUR

T1 - Analysis of mechanical properties and microstructure of single and double-pass friction stir welded T-joints for aluminium stiffened Panels

AU - Wagner, Douglas

AU - Bernardi, Matteo

AU - Grassel, Felix

AU - Chen, Ting

AU - Schimanski, Kai

AU - Bergmann, Luciano

AU - Klusemann, Benjamin

PY - 2024/11/5

Y1 - 2024/11/5

N2 - This study investigates the application of Friction Stir Welding (FSW) for fabricating stiffened structures in AA2219-T31 using a T-lap configuration. These structures are vital in various applications where weight is a crucial factor, including aircraft fuselages, railway cars and automotive parts. This study assesses the formation dynamics of lack of bonding in single-pass welds, including the examination of microstructure, hardness, mechanical properties, and fracture locations. A second welding pass was employed over the initial weld to eliminate the lack of bonding. The implementation of a second welding pass significantly improves joint efficiency, achieving up to 90 % of the ultimate tensile strength in the skin direction and 95 % in the stiffener direction, establishing a new benchmark for AA2219-T31 T-joints. Additionally, no significant differences in grain size were found between single- and double-pass welds, highlighting the lack of bonding as key factor affecting the strength of the joints. The proposed method offers valuable insights for future industrial applications to avoid defects such as lack of bonding.

AB - This study investigates the application of Friction Stir Welding (FSW) for fabricating stiffened structures in AA2219-T31 using a T-lap configuration. These structures are vital in various applications where weight is a crucial factor, including aircraft fuselages, railway cars and automotive parts. This study assesses the formation dynamics of lack of bonding in single-pass welds, including the examination of microstructure, hardness, mechanical properties, and fracture locations. A second welding pass was employed over the initial weld to eliminate the lack of bonding. The implementation of a second welding pass significantly improves joint efficiency, achieving up to 90 % of the ultimate tensile strength in the skin direction and 95 % in the stiffener direction, establishing a new benchmark for AA2219-T31 T-joints. Additionally, no significant differences in grain size were found between single- and double-pass welds, highlighting the lack of bonding as key factor affecting the strength of the joints. The proposed method offers valuable insights for future industrial applications to avoid defects such as lack of bonding.

KW - Friction stir welding

KW - T-Joint

KW - Aluminium alloy

KW - Mechanical behaviour

KW - Microstructure analysis

KW - Engineering

U2 - 10.1016/j.matdes.2024.113438

DO - 10.1016/j.matdes.2024.113438

M3 - Journal articles

JO - Materials and Design

JF - Materials and Design

SN - 0264-1275

ER -