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arXiv · 1412.7452

Cascade morphology transition in bcc metals

Wahyu Setyawan·Aaron P. Selby·Niklas Juslin·Roger E. Stoller·Brian D. Wirth·Richard J. Kurtz
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Abstract

Energetic atom collisions in solids induce shockwaves with complex morphologies. In this paper, we establish the existence of a morphological transition in such cascades. The order parameter of the morphology is defined as the exponent, $b$, in the defect production curve as a function of cascade energy ($N_F \sim E_{MD}^b$). Response of different bcc metals can be compared in a consistent energy domain when the energy is normalized by the transition energy, $\mu$, between the high- and the low-energy regime. Using Cr, Fe, Mo and W data, an empirical formula of $\mu$ as a function of displacement threshold energy, $E_d$, is presented for bcc metals.

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Wahyu Setyawan, Aaron P. Selby, Niklas Juslin, Roger E. Stoller, Brian D. Wirth, Richard J. Kurtz. 2014-12-23. Cascade morphology transition in bcc metals. https://doi.org/10.1088/0953-8984/27/22/225402

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