Pre-bond surface inspection using laser-induced breakdown spectroscopy for the adhesive bonding of multiple materials

Abstract

To inspect surface contamination of the surfaces for adhesive bonding, laser-induced breakdown spectroscopy (LIBS) was examined. A LIBS setup which gave an improved limit of detection (LOD) of 5.29 mg mm−2 was used for evaluation of Si contamination on steel and CFRP substrates. The LOD values obtained were 1.35 and 11.4 mg mm−2 for steel and CFRP, respectively. These LOD values were affected by several factors such as efficiency of energy transfer to Si and interference with trace substances included in the surface layer of substrates. Silicone included in the resin layers of CFRP was investigated by multiple pulse LIBS measurements.