Raising thermal stability of nanograins in a CuCrZr alloy by precipitates on grain boundaries

In this work, one group of solid solution CuCrZr alloy was pre-aged and followed by dynamic plastic deformation to prepare nanograins with randomly distributed precipitates and the other group of solid solution CuCrZr alloy was subjected to dynamic plastic deformation and followed by aging treatment to prepare nanograins with precipitates on grain boundaries. We investigated the effect of precipitate distributions on the nanograin growth in the strain-induced nanostructured CuCrZr alloy. The results showed that the onset temperature of nanograin growth is ~523 K when precipitates are distributed randomly in the nanograins. Grain growth occurs at 723 K for the nanograins with precipitates located on grain boundaries. The precipitates located on grain boundaries much enhance Zener pinning effect than those distributed randomly in the nanograins, thus raising the thermal stability of nanograins.