caa a22 4500 463234499 CHVBK 20180405153252.0 cr unu---uuuuu 170326e20070801xx s 000 0 eng 10.1007/s10853-006-1181-6 doi (NATIONALLICENCE)springer-10.1007/s10853-006-1181-6 Crack growth in structural adhesive joints in aqueous environments [Elektronische Daten] [A. Kinloch, C. Korenberg, K. Tan, J. Watts] The adhesive fracture energy, G c , of metallic joints, bonded with a rubber-toughened epoxy adhesive, has been measured using monotonically-loaded tests. Such tests have been conducted in various relative humidities and in water, at 21°C. Two surface pretreatments have been employed for the substrates prior to bonding: a simple grit-blast and degrease (‘GBD') pretreatment or a grit-blast, degrease and silane primer (‘GBS') pretreatment. The joints were formed using metallic substrates which were either (a) aluminium-alloy substrates, (b) steel substrates, or (c) ‘dissimilar' substrates (i.e. one substrate being aluminium-alloy with the other one being steel). For both test environments, when G c was plotted against the crack velocity, three regions of fracture behaviour could be distinguished. At low rates of displacement the crack grew in a stable manner, visually along the interface, and relatively low crack velocities could be readily measured. This was termed ‘Region I' and here the value of G c measured in the aqueous environment was relatively low compared to that measured in a relatively dry environment of 55% relative humidity. On the other hand, at relatively high rates of displacement the crack always grew in a stick-slip manner mainly cohesively in the adhesive layer at approximately 20km/min. This was termed ‘Region III', and here the value of G c was relatively high and independent of the environmental test conditions employed. In this region the crack was considered to grow faster than the water molecules were able to reach the crack tip, which explains the independence of G c upon the test environment. In between ‘Region I' and ‘Region III', a transition region was observed which was designated as ‘Region II'. The major effect of the ‘GBS' pretreatment, compared to the ‘GBD' pretreatment, was to increase the value of G c both in ‘Regions I and III', although the presence of the silane primer had the far greater effect in ‘Region I'. Springer Science+Business Media, LLC, 2007 Kinloch A. Department of Mechanical Engineering, Imperial College London, Exhibition Road, SW7 2AZ, London, UK aut Korenberg C. Department of Mechanical Engineering, Imperial College London, Exhibition Road, SW7 2AZ, London, UK aut Tan K. Department of Mechanical Engineering, Imperial College London, Exhibition Road, SW7 2AZ, London, UK aut Watts J. The Surface Analysis Laboratory, School of Engineering, University of Surrey, GU2 7XH, Guildford, Surrey, UK aut Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/15(2007-08-01), 6353-6370 0022-2461 42:15<6353 2007 42 10853 https://doi.org/10.1007/s10853-006-1181-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10853-006-1181-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kinloch A. Department of Mechanical Engineering, Imperial College London, Exhibition Road, SW7 2AZ, London, UK aut NATIONALLICENCE 700 1- Korenberg C. Department of Mechanical Engineering, Imperial College London, Exhibition Road, SW7 2AZ, London, UK aut NATIONALLICENCE 700 1- Tan K. Department of Mechanical Engineering, Imperial College London, Exhibition Road, SW7 2AZ, London, UK aut NATIONALLICENCE 700 1- Watts J. The Surface Analysis Laboratory, School of Engineering, University of Surrey, GU2 7XH, Guildford, Surrey, UK aut NATIONALLICENCE 773 0- Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/15(2007-08-01), 6353-6370 0022-2461 42:15<6353 2007 42 10853 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer