Effect of Adhesive Cure Schedule and Test Temperature on Tensile Shear Adhesion Strength of a High Carbon Steel

Effect of cure schedule and test temperature on tensile shear adhesion strength was investigated in a S55C high carbon steel/epoxy resin adhesive system, and was discussed the interrelations among shear, tensile and peel adhesion strengths. The results obtained are as follows :(1) Probability distribution of adhesion shear strength was found to be followed by Weibull distribution.(2) Shear strength obtained for various heating temperatures and its holding times, tested under 20°C, was divided into three stages in Larson-Miller parameter plot, that is, incomplete adhesion stage I of interface failure, suitable adhesion stage II of cohesive failure and deterioration adhesion stage III of cohesive-interface mixing failure mode.(3) The test temperature dependence on shear strength having peaks was observed and the fracture mode was cohesive failure below 40°C corresponding to the temperature of a maximum strength, whereas shear strength decreased gradually with the appearance of an interface failure above 40°C.(4) There lay a positive linear correlation between shear and tensile adhesion strengths, in addition to similar relationship between peel and tensile adhesion strengths.