A new technique for compression tests at intermediate strain rates: Prototype results

A prototype of a new concept for intermediate strain rate compression testing is presented. The concept uses elastic impact principles applied to a wedge mechanism to accelerate the actuation mechanism from rest to a test speed of 50 mm/s in approximately 133 mu s, and maintain a near uniform strain rate of 10 s(-1) to a strain of 0.2. The load frame is miniaturized and does not contain any hydraulic or pneumatic components and hence has a relatively high natural frequency of above 30 kHz, which improves the confidence with which signal processing techniques can be applied. Quasi-static and dynamic test results for commercially pure Aluminium are reported and the feasibility of future developments is discussed.