naa a22 4500 510771165 CHVBK 20180411083214.0 cr unu---uuuuu 180411e20130301xx s 000 0 eng 10.1007/s11837-012-0550-7 doi (NATIONALLICENCE)springer-10.1007/s11837-012-0550-7 Introducing Grain Boundary Influenced Stochastic Effects into Constitutive Models [Elektronische Daten] Application to Twin Nucleation in Hexagonal Close-Packed Metals [Stephen Niezgoda, Irene Beyerlein, Anand Kanjarla, Carlos Tomé] Twinning is an important deformation mechanism in hexagonal close-packed (hcp) metals such as Mg, Zr, Ti, and Be. Twinning in hcp materials is a multiscale process that depends on microstructural and mechanical response details at the mesoscale, microscale, and atomic scales. Twinning can generally be understood as a two-step process, a nucleation step followed by propagation. The nucleation of twins is governed by both material details such as the defect configurations at potential nucleation sites within grain boundaries, as well as the highly local mechanical field near grain boundaries. These two factors, the material and mechanical, must align for a successful nucleation event. In this article, we present a stochastic constitutive law for nucleation of twins and describe its implementation into a homogenized crystal plasticity simulation. Twin nucleation relies on the dissociation of grain boundary defects under stress into the required twinning partials. This dissociation is considered to follow a Poisson process where the parameters of the Poisson distribution are related to the properties of the grain boundaries. The rate of the process is a direct function of the local stress concentration at the grain boundary. These stress concentrations are randomly sampled from a distribution calibrated to full-field crystal plasticity simulations. TMS (outside the USA), 2013 Niezgoda Stephen Materials Science and Technology Division, Los Alamos National Laboratory, 87545, Los Alamos, NM, USA aut Beyerlein Irene Theoretical Division, Los Alamos National Laboratory, 87545, Los Alamos, NM, USA aut Kanjarla Anand Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, 600036, Chennai, India aut Tomé Carlos Materials Science and Technology Division, Los Alamos National Laboratory, 87545, Los Alamos, NM, USA aut JOM Springer US; http://www.springer-ny.com 65/3(2013-03-01), 419-430 1047-4838 65:3<419 2013 65 11837 https://doi.org/10.1007/s11837-012-0550-7 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11837-012-0550-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Niezgoda Stephen Materials Science and Technology Division, Los Alamos National Laboratory, 87545, Los Alamos, NM, USA aut NATIONALLICENCE 700 1- Beyerlein Irene Theoretical Division, Los Alamos National Laboratory, 87545, Los Alamos, NM, USA aut NATIONALLICENCE 700 1- Kanjarla Anand Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, 600036, Chennai, India aut NATIONALLICENCE 700 1- Tomé Carlos Materials Science and Technology Division, Los Alamos National Laboratory, 87545, Los Alamos, NM, USA aut NATIONALLICENCE 773 0- JOM Springer US; http://www.springer-ny.com 65/3(2013-03-01), 419-430 1047-4838 65:3<419 2013 65 11837 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer