Application of ultrasonic vibrations in welding and metal processing: A status review

Friction stir processing – State of the art

Modeling the effects of ultrasonic vibration on friction stir welding

The present article introduces the auxiliary energy assisted friction stir welding (FSW) processes purported to overcome the shortcomings of the conventional FSW process. The auxiliary energies used for this purpose are thermal energy from electric resistance heat, induction heat, laser, plasma, arc, etc. and mechanical energy in the form of ultrasonic vibration. The state-of-the-art, experimentation and progresses in these FSW variants are surveyed and compiled. The auxiliary energy assisted FSW processes exhibit great promise by having numerous advantages over the conventional FSW in terms improved process window, heat generation, material flow, reduced load on the tools and mechanical properties of joints. Such remarkable advantages would lead these processes to redefine many global technologies and markets in the twenty-first century. However, these variants are still in their preliminary stages of investigation, and more systematic investigations are necessary for their critical assessment. I...

Auxiliary energy assisted friction stir welding – status review

Local microstructure evolution in Al 6061-T6 friction stir weld nugget enhanced by ultrasonic vibration

Ultrasonic-assisted friction-stir welding is a new solid-state metal welding technology, based on friction-stir welding, in which weld performance is improved through application of ultrasound during welding. In this study, a model for the temperature field in 1.8 mm 2024 aluminum alloy is built based on computational fluid dynamics and elastic-plastic mechanics theory. Result show the impact of the ultrasound’s vibrations on the temperature field is less obvious at lower welding speeds. However, at higher welding speeds, it can provide the additional heat to keep sufficient welding temperature. The numerical results are compared with optical micrographs in order to validate the numerical models. Good agreement is obtained.

Yang Kunyu

Papers

A study of the temperature field during ultrasonic-assisted friction-stir welding