High strain rate elasto‐plasticity identification using the image‐based inertial impact (IBII) test part 2: Experimental validation

• Published in: Strain 2021-04, Vol.57 (2), p.n/a
• Main Authors: Fletcher, Lloyd, Davis, Frances, Dreuilhe, Sarah, Marek, Aleksander, Pierron, Fabrice
• Format: Article
• Language: English
• Subjects: Aluminum base alloys; Austenitic stainless steels; full‐field measurements; grid method; High strain rate; image‐based inertial impact test; Plastic properties; plasticity; Sensitivity; Stress-strain curves; ultra‐high speed imaging; virtual fields method
• ISSN: 0039-2103; 1475-1305
• DOI: 10.1111/str.12374

Current high strain rate testing techniques typically rely on the split‐Hopkinson bar (SHB). The early response in an SHB test is corrupted by inertia making it difficult to accurately characterise the transition from elasticity to plasticity for metals. Therefore, a new test method is required. This article is the second in a two‐part series which aims at developing a new high strain rate test for elasto‐plasticity identification using the image‐based inertial impact (IBII) method. The goal of this article is to validate the new method experimentally using IBII tests on aluminium 6082‐T6 (minimal rate sensitivity) and stainless steel 316L (rate sensitive). Comparison of the quasi‐static and dynamic stress–strain curves for the aluminium case showed minimal difference providing experimental validation of the method. The same comparison for the steel showed that the method was able to detect rate sensitivity.