THERMAL EFFECTS ON ADHESIVELY BONDED COMPOSITE REPAIR OF CRACKED ALUMINUM PANELS

This study introduces the two-dimensional finite element analysis invo lving three layer technique to investigate the adhesively bonded compo site: repair of cracked metallic structure under thermo-mechanical loa ding. The thermal loading involves, in this study, the temperature dro p such as seen during the bonding process. Three patch materials havin g different stiffnesses and coefficients of thermal expansion are inve stigated to analyze the thermal effects on the damage tolerance of the crack in the repaired structure and of the debond in the adhesive bon dline. For the single sided repair, the patch material having the maxi mum mismatch in the coefficient of thermal expansion with that of the cracked aluminum plate provides the better damage tolerance capability for both the crack in the panel and the debond in the adhesive. On th e other hand, for double sided repair, the patch material having the m inimal mismatch in the coefficient of thermal expansion with that of t he cracked plate provides the better damage tolerance capability.