Intermittent plasticity in individual grains: A study using high energy x-ray diffraction.

摘要: Long-standing evidence suggests that plasticity in metals may proceed an intermittent fashion. While the documentation of intermittency plastically deforming materials has been achieved several experimental settings, efforts to draw connections from dislocation motion and structure development stress relaxation have limited, especially bulk polycrystals. This work uses high energy x-ray diffraction measurements build these links by characterizing plastic deformation events inside individual grains both titanium alloy, Ti-7Al, magnesium AZ31. analysis is performed combining macroscopic data, complete grain states found using far-field microscopy, rapid spot made a Mixed-Mode Pixel Array Detector. Changes content within are monitored evolution full 3-D shapes intensity distributions reciprocal space. The results for Ti-7Al alloy show presence large fluctuations contrast AZ31, which shows lesser degree flow.