Mechanical Testing and Evaluation
High Strain Rate Testing
High strain rate testing is important for many engineering structural applications and metalworking operations. This article describes various methods for high strain rate testing. Several methods have been developed, starting with the pioneering work of John Hopkinson and his son, Bertram Hopkinson. Based on these contributions and also on an important paper by R.M. Davies, H. Kolsky invented the split-Hopkinson pressure bar, which allows the deformation of a sample of a ductile material at a high strain rate, while maintaining a uniform uniaxial state of stress within the sample.
This article reviews high strain rate compression and tension test methods with a focus on the general principles, advantages, and limitations of each test method. The compression test methods are cam plastometer test, drop tower compression test, the Hopkinson bar in compression, and rod impact (Taylor) test. The flyer plate impact test, expanding ring test, split-Hopkinson bar in tension, and a test using a rotating wheel used for high strain rate tension are also discussed.