The Influence of Selected Test Conditions on the Impact Strength of Adhesively Bonded Connections.

The conditions of adhesive connections testing can significantly affect the recorded findings. The standards, under which the investigations are conducted, do not take into account numerous factors that can greatly influence the outcome of the tests. Moreover, the research parameters in the standards are not specified. It is not defined in what manner their change, or any failure to comply with the standards, will affect test results. This article presents the results of experimental research, completed with numerical simulations, designed to test to what extent the recorded impact strength of adhesive connections is affected by the stiffness of the test stand, and the speed and energy of the impactor. In the experimental research, the authors used block samples whose substrates were made of an aluminum alloy. The elements of the samples were bonded by means of three different epoxy adhesives. The models used in numerical calculations were built on the basis of the real dimensions of the specimens used in this experimental research. As a result of the performed tests and conducted calculations, it was found that the use of test stands of lesser stiffness resulted in an increased registered impact strength due to an increased energy value of elastic deformations.