| Popis: |
The influence of subgrain size, λ, on the creep strength, σ. of high purity polycrystalline aluminum was studied by a unique method involving instantaneous strain rate change tests. The results obtained reveal that the strength at a given strain rate increases as the subgrain size decreases following the relation σ ∝ λ − p / N , where p and N are creep parameters about equal to 3.2 and 7.4 respectively. These values of p and N are in close agreement with those obtained from stress reduction tests in creep experiments. Attention is drawn to the need for new creep models which identify the importance of subgrain boundaries to the creep process. |
