Materials testing at high constant strain rates

An improved version of the split-Hopkinson pressure bar system for materials testing at high rates of loading is described. This new system has a preloading bar together with a pulse-shaping dummy specimen of the same material as the test specimen. Using the transmitted pulse through the pulse shaper as a tailored incident pulse for loading the test specimen enables testing to be carried out at virtually constant rates of strain, from about 100 s-1 to 300 s -1. This represents a significant improvement over the normal method where there can be considerable variation in strain rate throughout a test with a consequent uncertainty in the interpretation of the results.