Deformation behavior in bulk nanocrystalline-ultrafine aluminum: in situ evidence of plastic strain recovery

摘要

The plastic deformation behavior of bulk nanocrystalline-ultrafine Al was investigated under in situ compressive loading using high-energy synchrotron X-ray diffraction. After one loading-unloading cycle, to 2 percent strain, we find reversible peak broadening within the nanocrystalline grain volume and tensile residual stress (80 MPa) within the ultrafine grain volume. Upon unloading, we detect recovery of 12 percent of the plastic strain, and this recovery increases up to 28 percent at even higher applied deformations to 4 percent.