Compression Testing and Buckling

Abstract

In compression, materials exhibit elastic deformation similar to that found in tension. In the compression mode another deformation behavior becomes possible, the buckling failure of the sample. For long, slender samples the buckling failure may occur at a lower applied load than plastic deformation and the design of a structure must involve this load limit. If the sample is subjected to a "deadweight" load it will collapse under this load if it is larger than the critical load for buckling. If the test is performed at constant strain rate, the testing machine reduces the load to the value required to maintain the deformation rate and the sample is stable in the buckled configuration. For large deformations, plastic buckling occurs and the material is permanently deformed. This experiment will study these behavior modes for a slender rod sample and tubes that exhibit plastic buckling.