Materials Characterization at High Speed by Dynamic Tensile Tests

Abstract

In this paper, the dynamic deformation behaviors of 2 aluminum alloys (AA6016, AA5182) and 2 steels (v 1158, FeP04) are investigated. Firstly, the test method, an improved Hopkinson pressure bar test, is introduced. Then, the test results are presented and analyzed. The strain rate range used in this study is between 290 s^(-1) and 1750 s^(-1).The test results show that the yield stresses of all four tested materials increase along with the increase of strain rate, but the ductility does not. An interesting finding is that the tested Al alloys demonstrated larger elongation than those of steels. In conventional tensile tests, as it is well known, the tensile elongation of low carbon steels is usually much higher than the one of Al alloys. So, it can be predicted that the aluminum alloys could have better formability than the steels in high speed forming processes, though the underlying mechanism is not fully understood.