Laser direct joining of carbon fibre reinforced plastic tostainless steel

Abstract

This study was performed to evaluate the characteristics and strengthsof dissimilar joints between carbon fibre reinforced plastics (CFRP)and stainless steel using high brightness continuous wave disc laser. Tensileshear tests demonstrated that strong CFRP steel joint with ∼4800 N couldbe produced. The joints were tightly bonded on atomic or molecular sized levelthrough Cr–Fe oxide film on the metal surface, and small fragments oftype 304 steel were detected on the fractured CFRP. Many bubbles of submillimetresize were formed all over the plastic melted zone in the CFRP. The gas compositionsinside the bubbles were H2 and hydrocarbon series as pyrolysisgases of the CFRP as well as N2 in air. These results suggest strongchemical and physical bonding of the CFRP on the oxide film of the type 304plate. Consequently, it was confirmed that a strong joint could be producedbetween CFRP and type 304 stainless steel with a laser beam.