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Collaborative Modeling and Experimental Research Program to Understand the Dynamics of Dislocation - Particle Interactions, DMR 0244562 Ian M. Robertson, University of Illinois, Urbana-Champaign B.D. Wirth, University of California, Berkeley.
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Collaborative Modeling and Experimental Research Program to Understand the Dynamics of Dislocation - Particle Interactions, DMR 0244562 Ian M. Robertson, University of Illinois, Urbana-Champaign B.D. Wirth, University of California, Berkeley Combination of experimental and simulation techniques has developed new understanding of dislocation - precipitate interactions, in particular revealing the copper precipitate strengthening in iron due to a reversible structural phase transformation1, and refuting the supposition that high strain rate deformation can occur without dislocation - based plasticity. Bubble raft models have been developed to gain additional insight to interaction processes between dislocations and precipitates. Defect structure in Al deformed in-situ at high displacement rate shows defects and dislocations existing in the thinned ligament. a) ligament, b and c) higher magnification images of defect structure. 1 J.-H. Shim, Y.W. Cho, S.C. Kwon, W.W. Kim, and B.D. Wirth, App Phys Lett90 (2007) 012906. Dislocation impacting a incoherent precipitate in a bubble raft. The arrow indicates a mobile defect.