Effect of tool shoulder features on defects and tensile properties of friction stir welded aluminum 6061-T6.

Six unique tool shoulder designs were produced with the objective of improved metal constraint and flow to the pin. The six tools were made of Ti–6Al–4V by metallic additive manufacturing. Each tool was used to produce butt welds using aluminum 6061-T6 plates. The welds were subjected to nondestructive evaluation and tensile testing to determine weld soundness and strength. A FSW tool shoulder having a raised spiral design produced the weld with the best combination of surface quality and mechanical properties. The additive-manufactured Ti–6Al–4V tooling had good wear characteristics and appears to be a suitable route to rapidly produce unique FSW tool designs. [ABSTRACT FROM AUTHOR]