In this paper, the cyclic stress amplitude-controlled fatigue response and fracture characteristic of a copper-niobium microcomposite based on an oxide dispersion strengthened matrix are presented and discussed. The microcomposite samples were deformed cyclically over a range of maximum stress, at both ambient and elevated temperatures, and at two different stress ratios. At a given stress ratio, an increase in test temperature was observed to have a detrimental influence on cyclic fatigue life of the microcomposite. At a given temperature the cyclic fatigue resistance degraded with a decrease in stress ratio The influence of ductile phase reinforcement on high cycle fatigue response, and fracture behavior of the material is discussed in light of the specific roles of intrinsic microstructural effects, maximum stress, stress ratio, test temperature and macroscopic aspects of fracture.
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