Residual Strains of 0.04% Carbon Steel due to Passage of a Single Pulse Compression Stress Wave

抄録

Under the longitudinal compressive impact of steel bars, a single pulse stress wave which is most fundamental for the investigation of impact failure of materials was obtained. Making such a stress wave repeatedly pass through a cylindrical specimen of 0.04% carbon steel, we determined some experimental relations between the amplitude of stress and its duration, and residual strains measured with resistance wire strain gages bonded on the specimen. The experiments were carried out under the stress wave of which the amplitude was varied from static yield point to twice that, duration from 200 μsec to 600 μsec and the number of repetitions was less than 100. Residual strains are influenced by the amplitude of stress and its duration. The larger is the amplitude and also the longer the duration, the larger become the residual strains. They increase as the number of repetitions rises, but at certain number they increase radically. This phenomenon is due to the spread of plastic deformation from both ends of the specimen.