100 Years and Still Cracking: A Griffith Fracture Symposium: Poster Session
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Nanomechanical Materials Behavior Committee
Program Organizers: Megan Cordill, Erich Schmid Institute of Materials Science; William Gerberich, University of Minnesota; David Bahr, Purdue University; Christopher Schuh, Northwestern University; Daniel Kiener, Montanuniverstität Leoben; Neville Moody; Nathan Mara, University of Minnesota; Erica Lilleodden, Fraunhofer Insitute for Microstructure of Materials and Systems (IMWS)
Tuesday 5:30 PM
March 16, 2021
Room: RM 47
Location: TMS2021 Virtual
Session Chair: Megan Cordill, Erich Schmid Institute
Crack Driving Force Expressions Using Compliance Approach in Clamped Beam Bending Geometry: Tejas Chaudhari1; Ashwini Mishra1; Hrushikesh Sahasrabuddhe1; Nagamani Jaya Balila1; 1IIT Bombay
The geometric stability for controlled crack growth is shown, and stress intensity factor solutions are derived in single edge-notched clamped beam specimens (SENCB) in the previous work. In the present study, numerical simulations are carried out through an extended finite element method (XFEM) to derive crack driving force solutions for different beam aspect ratios (L/W) and elastic moduli (E). In the case of linear elastic fracture mechanics (LEFM), the crack driving force is also known as the energy release rate (G). The expressions for G are derived using an energy-based compliance approach, which is more convenient to execute in a realistic scenario. The variations in G with crack length (a) through the compliance approach are compared with those obtained directly from XFEM. Experimental validation of the G obtained has also been carried out at the macro-scale using a linear elastic material poly-methyl methacrylate (PMMA).
EAM Potential for Liquid Metal Induced Fracture: Antoine Clement1; Thierry Auger1; 1CNRS / PIMM
Here we aim at modeling the competition between dislocation emission at a crack tip with fracture "ā la Griffith" for alpha brass in contact with a liquid metal. This requires computing generalized stacking fault energies in Cu-Zn alloys. An EAM (Embedded Atom Method) potential has been developed for this purpose for the fcc phase only. Calculations by DFT-GGA of various physical quantities (Cij, vacancy, ...) have been used to fit the potential. Zinc is being modelled in its fcc state so that the potential is valid only for the alpha phase. Copper and zinc are treated with the same cut-off to be consistent in the alloy. Preliminary results (Solid solution hardening and extension towards fracture) using this potential will be shown as well as a comparison with experimental data on liquid metal induced fracture. Thermodynamics (mixing enthalpy) of Cu-Zn and mechanical (stacking fault energy) properties are well reproduced.