This press release describes two large scale atomic simulations carried out by IBM and LLNL researchers in 2002. Two 20 million atom simulations were carried out with interatomic forces which were harmonic (constant with stress, spring-like) and anharmonic (increasing with stress, rubbery polymers), respectively. Simulation videos showing the resulting crack propagation are shown. In the anharmonic case, the crack propagation is supersonic. Also, a one billion atom simulation was carried out with interatomic forces set to represent ductile behavior. A simulation video is shown which demonstrates the resulting evolution of a tangled dislocation network; i.e. work hardening behavior.

Citation: "IBM and LLNL Scientists Show Supercomputer Advance in Predicting Materials Strength," IBM Research. San Jose, CA. April 30, 2002.

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