Friction stir vibration brazing (FSVB): an improved version of friction stir brazing

Friction stir vibration brazing (FSVB) by application of mechanical vibration was introduced in this investigation. In the current research, the adjoining samples are vibrated normally to the brazing line while FSB is performed. Low carbon steel sheets are joined together using FSB and FSVB while SiC nanoparticles are also incorporated in the joint. The microstructure and mechanical behavior of the joints developed under different conditions are analyzed. %67wt Sn-%33wt Pb alloy is used as braze metal. The results show that the strength of the friction stir vibration brazed specimens is higher than that of the friction stir brazed specimens. The vibration of adjoining specimens, during FSVB, enhances the eutectic reaction of the melt braze metal between the adjoining specimens and the melt fills the space between adjoining specimens thoroughly. By introducing vibration during the FSB process, both strain rate and temperature which have fundamental effects on the characteristics of the joints, increase. The results indicate that the strength and the hardness of FSVB-ed samples increase and the grain size decreases as vibration frequency increases from 30 to 60 Hz. In addition, the thickness of IMCs in the joint interface decreased to around 0.7 µm as the vibration frequency increased.