Compression properties and impact energy release characteristics of TiZrNbV high-entropy alloy

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 827; p. 142074
• Main Authors: Ren, Kerong, Liu, Hongyang, Chen, Rong, Tang, Yu, Guo, Baoyue, Li, Shun, Wang, Jie, Wang, Ruixin, Lu, Fangyun
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 19.10.2021; Elsevier BV
• Subjects: Brittle fracture; Chemical energy; Chemical reactions; Compression behavior; Compression loads; Compressive properties; Computer simulation; Constitutive models; Direct ballistic test; Edge dislocations; Finite element method; Finite element simulation; High entropy alloys; High temperature; High-entropy alloy; Impact energy release characteristics; Impact loads; Mathematical models; Microstructure; Numerical methods; Oxidation; Shear bands; Split hopkinson pressure bars; Strain rate; Temperature profiles; Direct ballistic test; Compression behavior; Split hopkinson pressure bars; Impact energy release characteristics; High-entropy alloy; Finite element simulation
• ISSN: 0921-5093; 1873-4936; 1873-4936
• DOI: 10.1016/j.msea.2021.142074

To explore the potential of high-entropy alloys (HEAs) as energetic structural materials (ESMs), the compression behaviors and impact energy release characteristics of TiZrNbV HEA were investigated. Mechanical experiments at strain rates from 1 × 10−3 s−1 to 1 × 104 s−1 showed that TiZrNbV HEA exhibits clear dynamic brittle fracture behavior under dynamic compression loading, which is diametrically opposite to its behavior under quasi-static compression loading. A Johnson–Cook constitutive model for TiZrNbV HEA was obtained by fitting the experimental data, which demonstrated an apparent strain rate effect. Numerical simulation and microstructure results revealed the role of an adiabatic shear band (ASB) in the brittle fracture. The crack profiles that evolved from the ASB exhibited the typical characteristic for high temperatures. The degree and rate of the chemical reaction and recycled products of direct ballistic tests indicated that severe oxidation reactions induced by the high-temperature profiles resulted in chemical energy release under impact loading. The relationship between the material microstructure and macromechanical behavior of TiZrNbV HEA, which is important in the use of HEAs as ESMs, was revealed in this study through mechanical and material methods and finite element numerical simulation. •TiZrNbV alloy had a single-phase BCC with no preferred grain orientation.•A Johnson–Cook constitutive model was obtained by data fitting.•The alloy exhibited brittle fracture behavior under dynamic compression loading.•Adiabatic shear may play an important role in stress collapse and brittle fracture.•High-temperature oxidation results in chemical energy release under impact loading.