Climb Enabled Discrete Dislocation Plasticity of Superalloys

Abstract:

Ni-based superalloys comprising of elastic particles embedded in a single crystal elastic-plastic matrix are usually subject to loading at elevated service temperatures. In order to enhance the understanding of high temperature deformation mechanisms a two dimensional discrete dislocation plasticity framework wherein the dislocations movement that incorporates both glide and climb is formulated. The climbing dislocations are modelled as point sources/sinks of vacancies and the vacancy diffusion boundary value problem is solved by superposition of the vacancy concentration fields of the point sources/sinks in an infinite medium and a complementary non-singular solution that enforces the relevant boundary conditions. The vacancy concentration field along with the Peach-Kohler force provides the climb rate of the dislocations.

• Periodical: Key Engineering Materials (Volumes 651-653)
• Pages: 981-986
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.651-653.981
• Online since: July 2015
• Authors: Can Ayas*, Vikram Deshpande
• Keywords: Climb, Discrete Dislocations, Plasticity, Superalloys, Vacancy Diffusion

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