IT may be shown theoretically that when plane mechanical pulses of finite amplitude travel in non-dispersive media, the velocity of propagation in space is given by c + V where c = (S/ρ)1/2, S being the tangent modulus of the material and ρ its density, and V is the particle velocity associated with the pulse. If S increases with increasing amplitude of deformation, the head of the pulse will become steeper as it travels through the medium and it will eventually become a shock front, the gradient of which is limited by dissipative processes, such as internal friction and thermal conductivity. Such compressive shock waves are well known in fluids and in recent years similar shock waves have been produced and studied in blocks of solids1.
In a Kolsky bar, a sample is sandwiched between the incident and transmission bar. When the striker bar impacts the incident bar, an elastic compressive stress wave is generated. This stress wave travels through the incident bar. Upon reaching the incident bar and specimen interface, part of the wave is reflected and some part of it is transmitted through the specimen into the transmission bar (Figure 2). The pulse profile for the incident, transmitted, and reflected waves are recorded as a function of time. This pulse profile is further analyzed to determine the dynamic stress strain response of the specimen . A Kolsky bar setup is customized in different ways to allow for the testing of a wide variety of materials. 1e1e36bf2d