STRESS CYCLE TESTING DURING CREEP OF A PARTICLE-STRENGTHENED NB-1ZR-0.1C ALLOY

Stress cycle testing was performed during high-temperature creep of a particle-strengthened alloy of niobium (Nb-1Zr-0.1C). Two methods were used to analyze the data from the stress cycles to determine the back stress arising from the dislocation substructure as a function of app lied stress, temperature, and accumulated strain. Back stresses as hig h as 96% of the applied stress were measured. In general, the normaliz ed effective stress, calculated from the dislocation back stress, was shown to be independent of the applied stress and temperature.