Unraveling the Anomalous Grain Size Dependence of Cavitation

J. W. Wilkerson and K. T. Ramesh

Phys. Rev. Lett. 117, 215503 – Published 17 November 2016

Abstract

Experimental studies have identified an anomalous grain size dependence associated with the critical tensile pressure that a metal may sustain before catastrophic failure by cavitation processes. Here we derive the first quantitative theory (and its associated closed-form solution) capable of explaining this phenomena. The theory agrees well with experimental measurements and atomistic calculations over a very wide range of conditions. Utilizing this theory, we are able to map out three distinct regimes in which the critical tensile pressure for cavitation failure (i) increases with decreasing grain size in accordance with conventional wisdom, (ii) nonintuitively decreases with decreasing grain size, and (iii) is independent of grain size. The theory also predicts microscopic signatures of the cavitation process which agree with available data.

Received 15 August 2016

DOI:https://doi.org/10.1103/PhysRevLett.117.215503

Physics Subject Headings (PhySH)

Equations of state Fracture Grain boundaries Material failure Plastic deformation Plasticity Shock waves

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

J. W. Wilkerson¹ and K. T. Ramesh²

¹Department of Mechanical Engineering, University of Texas at San Antonio, Texas 78249, USA
²Hopkins Extreme Materials Institute, The Johns Hopkins University, Baltimore, Maryland 21218, USA