Material Characterization at High Strain by Adapted Tensile Tests

• Published in: Experimental mechanics Vol. 52; no. 8; pp. 1195 - 1209
• Main Authors: Emmens, W. C., van den Boogaard, A. H.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.10.2012; Springer
• Subjects: Biomedical Engineering and Bioengineering; Characterization and Evaluation of Materials; Control; Cross-disciplinary physics: materials science; rheology; Dynamical Systems; Engineering; Exact sciences and technology; Fracture mechanics (crack, fatigue, damage...); Fundamental areas of phenomenology (including applications); Lasers; Materials science; Materials testing; Measurement and testing methods; Optical Devices; Optics; Photonics; Physics; Solid Mechanics; Structural and continuum mechanics; Vibration; Material characterization; Adapted tensile test; Work hardening; CBT test; Large strain; Materials testing; High strain; Brass; Tensile tests; Test bar; Plastic limit; Yield strength; Strain hardening; Breaking test; Inhomogeneous materials; Strength of materials; Bending test; Metering
• ISSN: 0014-4851; 1741-2765
• DOI: 10.1007/s11340-011-9577-x

The strength of materials at high strain levels has been determined using the so-called Continuous-Bending-under-Tension (CBT) test. This is a modified tensile test where the specimen is subjected to repetitive bending at the same time. This test enables to create high levels of uniform strain. A wide variety of materials has been tested this way. The strength of the material after CBT testing has been measured in different ways: by secondary tensile tests, by interrupted CBT tests, and directly from the fracture in the CBT test. All methods yield similar results: the strength is largely unaffected by the cyclic pre-deformation and mainly depends on the overall increase in length. Only for multi-phase materials the strength shows a minor influence of CBT test conditions. The hardening follows the extrapolated hardening observed in a conventional tensile test, except for brass. This test method can potentially be used for measuring hardening curves at high strain levels.