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Indexed by:Journal Papers

Date of Publication:2024-06-14

Journal:Journal of the Brazilian Society of Mechanical Sciences and Engineering

Volume:45

Issue:6

ISSN No.:1678-5878

Key Words:FSW; 2219 aluminum alloy; Thick plate; Temperature; Double-sided composite

Abstract:The heavy-lift launch vehicle fuel tank is composed of 2219 high-strength aluminum alloy, which is welded by friction stir welding (FSW) process. Nowadays, thickness of the advanced tank reaches 18 mm. When the thickness of 2219 aluminum alloy increases, temperature difference along the thickness increases, which is hard to guarantee the welding quality. This paper investigates temperature distribution of FSW thick 2219 aluminum alloy plate using numerical simulation and optimizes welding process parameters and tool geometric parameters. A simulation model of single-shoulder FSW is established using ABAQUS based on coupled Eulerian–Lagrangian (CEL) formulation, and the validity of the model is verified by experiment. The tool geometric parameters including shoulder diameter, thread angle, shoulder concavity and cone angle of the pin are optimized with minimum temperature difference along the thickness in the core area of the weldment as the optimization objective. A simulation model of double-sided composite FSW is established and the temperature field presents ‘dumbbell’ shape. The optimized combination of welding process parameters and tool geometric parameters including shoulder diameter, welding speed, rotational speed and rotational direction of the tool is obtained. The influence of the relative distance between the axis of the bilateral tools on the welding temperature field is examined. This study provides guidance for the selection of welding parameters and tool geometric parameters of FSW thick 2219 aluminum alloy plate.