Failure strain of expanding ring and its application to other expanding bodies

Abstract
The expanding ring experiment is a good tool to investigate the mechanical behavior of materials under high strain-rate loading, specifically strength and failure models. This paper illustrates a method to find the ring circumferential strain at failure, using both experimental results and plasto-dynamic calculations. The failure strains of OFE Copper, SST304 stainless steel and Tantalum rings are found. We present a correlation function between the failure strain of a ring and the failure strains of expanding cylindrical and spherical shells of the same material. This function is calibrated using published results and validated by predicting the failure strain of a SST304 stainless steel expanding cylinder, using the expanding ring failure strain found earlier.