REPUBLIC OF SERBIA

MINISTRY OF DEFENCE

www.mod.gov.rs

MINISTRY OF DEFENCE

Material Resources Sector

Defensive Technologies Department

Military Technical Institute

www.vti.mod.gov.rs

Influence of process parameters on tunnel type defect appearance and weld quality in FSW welded Al 2024 plates

Igor Radisavljević

Military Technical Institute, Belgrade, Serbia, igra@sbb.rs

Nenad Radović

Faculty of Technology and Metallurgy, Belgrade, Serbia

Vencislav Grabulov

IMS, Belgrade, Serbia

MILUTIN NIKAČEVIĆ

Military Technical Institute, Belgrade, Serbia,

Abstract: Some experiences in elimination of tunnel type defect Friction Stir Welded Al alloy 2024-T351 are presented in this paper. In order to evaluate the influence of the processing parameters (ratio between rotation and welding speed) on the occurrence of tunnel type defects and quality of welded joint, different welding parameters were varied. Welded joints were tested by means of both, non-destructive (visual, penetrant, X-ray and ultrasonic inspection) and destructive (metallographic, tension and hardness) testing. Sound joint obtained in wider R/V ratio between 5.00 and 25.65. Results suggest that with this ratio, material flows around the pin with optimal speed, i.e. sufficient amount of material is available to fulfill the gap and prevent tunnel formation, which leads to quality joint produce.

Key words: friction stir welding, al alloys, welding parameters, heat input, welding quality.