Compressive properties of ‹110› Cu micro-pillars after high-dose self-ion irradiation

Single-crystal Cu micro-pillars were self-ion irradiated up to 190 displacements per atom, a level commensurate with damage expected after long exposure in a reactor environment. Compression experiments performed along the ‹110› to 10% strain were compared against un-irradiated Cu. Two specimen configurations were explored: large 10μm tall and small 4μm tall pillars. Compared to un-irradiated Cu, the small irradiated pillars exhibited a flow stress increase of more than 500 MPa and were able to attain peak stresses approaching 1 GPa. These results are discussed in the context of an end of range effect, a damage gradient effect, and size effects.