Influence of Large Strain Reverse Loading on Dynamic Strain Localization and Failure of Ductile Metallic Rods

A bespoke real time strain control setup is constructed to apply the reverse loading directly to the gauge section of 304L stainless steel specimen up to a maximum strain level of ±0.16. The subsequent tensile tests of the reverse loaded specimens are performed from quasi-static to high strain rates of 1000 /s. A higher strain reverse loading significantly influences the development of necking instabilities, with smaller strain to necking inception, higher local stress in the necking zone, and higher local strain rate up to failure. An analysis of the local stress-strain relationship indicates that the reverse loaded 304L rod shows good impact energy absorption up to failure, which agrees with the ductile fracture surfaces of the 304L materials with reverse loading.