ISIM Achievements Regarding Friction Stir Welding in Inert Gas Environment

Abstract

Friction stir welding (FSW) is an important research direction within ISIM Timisoara. Also within ISIM Timisoara, in addition to the classic FSW welding, processes and methods derived from FSW were also approached. Those processes and methods include friction stir processing (FSP), coatings with functional layers by friction, conventional friction riveting and friction riveting with hybrid effect, hybrid welding methods: TIG assisted friction stir welding FSW-TIG and ultrasonic assisted friction stir welding FSW-US. Recent research were focused on a new method of applying the FSW process, namely friction stir welding in inert gas environment (FSW-IG). Results obtained by ISIM in the field of FSW-IG welding are presented: data / information on solutions for applying inert gas in the welding area, as well as experimental results obtained for FSW-IG welding of DD13 steel, Cu99 copper and AZ31B magnesium alloy respectively. The solutions for providing shielding gas in the welding area were analyzed, verified and validated by experiment. The experimental welding programs generated the necessary data for the development of the FSW-IG welding technologies for the approached materials. By applying FSW-IG welding there was an improvement in the aspect of the welded joints and for some of mechanical characteristics (as the case may be) compared to the application of classic FSW welding. The use of shielding gas also had beneficial effects on the service life of FSW tools.