The experimental investigation of high strain rate fragmentation has generally been limited to one of two cases: analytically powerful but simple one-dimensional loading configurations, or complicated multiaxial experiments more closely approximating use applications. The former, exemplified by Mott style ring fragmentation, promotes simple and confident analysis—forming the backbone of the field and revealing the basic nature of dynamic fragmentation in solids—but sacrifices nuance to achieve that simplicity. The latter, while informing applications of interest such as ballistic impact, can confound basic scientific investigation due to its myriad complexities and is often difficult to access diagnostically. This work presents an attempt to help bridge the gap between 1D ring expansion and 3D fragmentation experiments in the form of impact driven dynamic tensile biaxial fragmentation experiments, conceptually similar to quasi-static hydraulic bulge or hemispherical punch tests in ductile metals. Using this method, the fragmentation behavior and high strain rate ductility of annealed Ti-6Al-4V is investigated at tensile strain rates of 104-105 s-1. The deformation of the specimen and fragmentation pattern are observed by ultra-high-speed optical imaging and individual fragments are recovered and characterized post-mortem.
2021-04-07 08:00:00
