SPECTROSCOPIC AND MECHANICAL EVIDENCE OF THE INFLUENCE OF THE SUBSTRATE ON AN ANAEROBIC ADHESIVE CURE

The catalytic effect of different substrates-steel, aluminium and copp er-on the curing reaction of a standard anaerobic adhesive is investig ated by infrared microscopy in reflection mode. Thus, kinetics of the cure reaction, studied from the decrease of the carbon-carbon double b onds absorption peak, are quite different depending on the substrate u nder investigation. Among the studied metals, copper has been found as the most reactive surface. The assumed role of saccharine contained i n the anaerobic adhesive which is able to oxidise metals into ions wil l be highlighted. Finally, an attempt will be made to correlate the ki netic results with the mechanical performances of the adhesive joint m easured by a single lap shearing test. Thus, fast curing reaction of t he anaerobic adhesive on a surface such as copper leads to poor maxima l strain while lower surface reactivity may provide better mechanical performances of the adhesive joints. (C) 1997 Elsevier Science Ltd.