On the solid-state-bonding mechanism in friction stir welding. (May 2020)

• Record Type: Journal Article
• Authors: Wang, Xue; Gao, Yanfei; McDonnell, Martin; Feng, Zhili
• Is Part Of: Extreme mechanics letters. Volume 37(2020)
• Publication Date: 2020-05
• Subjects: Friction stir welding -- High temperature bonding -- Creep-controlled cavity closure; Mechanics -- Periodicals; Mechanics, Applied -- Periodicals; Mechanics; Electronic journals; Periodicals; 531.05
• DOI: 10.1016/j.eml.2020.100727
• Languages: English
• ISSNs: 2352-4316

Abstract

Abstract: A critical assessment of various solid-state-bonding mechanisms is established for friction stir welding (FSW) processes of engineering alloys. The commonly assumed sintering-like diffusional-bonding hypothesis is criticized in this work as not the dominant mechanism. For the wide spectrum of material constitutive laws and FSW processing conditions examined and employed in realistic applications, the thermomechanical history on the workpiece–workpiece interface traverses in the creep-dominated regime for the growth/shrinkage of interfacial cavities. The evolution of the bonding fraction relies mainly on the creep strain rate in the adjourning workpieces, weakly on stress triaxiality, and negligibly on interfacial diffusion.