Polymer Engineering Faculty Research

The effects of inherent flaws on the time and rate dependent failure of adhesively bonded joints

Erol Sancaktar, The University of Akron


Experiments on single lap joints bonded with viscoelastic adhesives reveal that the effects of rate and time and inherent flaws are as critical in joint failure as are the environmental and stress concentration effects. Experimental data reveal that random inherent flaws and loading rate changes may result in as much as 40 percent reduction in joint strength. Furthermore when creep loading is used, the asymptotic creep stress, below which no delayed failure will occur, may have to be as much as 45 percent less than the adhesive maximum strength.