Study of mechanisms of time-dependent crack growth at elevated temperature: Second annual progress report, February 16, 1987-February 15, 1988

The objective of this study is to conduct creep and creep-fatigue carck growth tests and to characterize the crack tip damage mechanisms in a model material (copper with 1 wt percent antimony) which is known to cavitate at the grain boundaries under creep deformation. The above data and observations will be used to develop mechanistic models for cumulative crack tip damage under complex loading conditions at elevated temperatures. The application of these models will also be extended to situations involving non-periodic loading. 6 refs., 16 figs.