Tensile cracks can shatter classical speed limits

• 成果类型: Article
• 署名作者: Wang, Meng; Shi, Songlin; Fineberg, Jay
• 署名单位: Hebrew University of Jerusalem
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-13301
• DOI: 10.1126/science.adg7693
• 发表日期: 2023-07-28
• 页码: 415-419
• 关键词: supershear rupture; dynamic fracture; sub-rayleigh; velocity

摘要

Brittle materials fail by means of rapid cracks. Classical fracture mechanics describes the motion of tensile cracks that dissipate released elastic energy within a point-like zone at their tips. Within this framework, a classical tensile crack cannot exceed the Rayleigh wave speed, cR. Using brittle neo-hookean materials, we experimentally demonstrate the existence of supershear tensile cracks that exceed shear wave speeds, cR. Supershear cracks smoothly accelerate beyond cR, to speeds that could approach dilatation wave speeds. Supershear dynamics are governed by different principles than those guiding classical cracks; this fracture mode is excited at critical (material dependent) applied strains. This nonclassical mode of tensile fracture represents a fundamental shift in our understanding of the fracture process.