A voidÐcrack nucleation model for ductile metals
نویسندگان
چکیده
A phenomenological voidÐcrack nucleation model for ductile metals with second phases is described which is motivated from fracture mechanics and microscale physical observations[ The voidÐcrack nucleation model is a function of the fracture toughness of the aggregate material\ length scale parameter "taken to be the average size of the second phase particles in the examples shown in this writing#\ the volume fraction of the second phase\ strain level\ and stress state[ These parameters are varied to explore their e}ects upon the nucleation and damage rates[ Examples of correlating the voidÐcrack nucleation model to tension data in the literature illustrate the utility of the model for several ductile metals[ Furthermore\ compression\ tension\ and torsion experiments on a cast AlÐSiÐMg alloy were conducted to determine voidÐcrack nucleation rates under di}erent loading conditions[ The nucleation model was then correlated to the cast AlÐSiÐMg data as well[ Þ 0888 Elsevier Science Ltd[ All rights reserved[
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