Fatigue properties of dissimilar FSSW joint between CFRP coated with steel mesh and Al alloy

Abstract

Lap joints between an A6061 Al alloy plate and a CFRP plate coated with a stainless steel wire mesh were fabricated using the friction stir spot welding (FSSW) technique. Three kinds of meshes, an SUS316L single layer mesh (316SL), an SUS316L double layer mesh (316DL) and an SUS329J1 single layer mesh (329SL), were used. Fatigue tests were conducted using the fabricated Al/CFRP joints and fatigue behavior was investigated. All of the three joints exhibited comparable fatigue strengths in the low cycle fatigue region, while the fatigue strength of Al/CFRP316SL was lower than those of Al/CFRP316LDL and Al/CFRP329SL. This indicates the fatigue strength of the joint is dependent on the strength of the mesh that coats the CFRP.