Creep-fatigue behavior of annealed Cu-Cr-Zr alloy tested at 650 K and 750 K

摘要

JAXA has been developing a new liquid rocket engine that utilizes a Cu-Cr-Zr alloy in the inner cylinder of its combustion chamber because of its high thermal conductivity and good fatigue resistance. The inner cylinder is exposed to high thermal stress, which results in early material failure. Previous experimental work has been carried out to understand the creep behavior and damage mechanisms of the Cu-Cr-Zr alloy for creep-fatigue (CF) cycles representative of a peak service temperature of 750 K. Since there exists some uncertainty in the component's local temperature distribution and since CF damage mechanisms are sensitive to slight variation in stress and temperature, a wider range of testing conditions has to be explored. At lower temperatures, such as 650 K, it is thought that damage will accumulate more quickly as recovery will not happen as readily.The objectives of this study are 1) to characterize the creep behavior Cu-Cr-Zr alloy at 650 K and 2) to compare the results to those obtained at 750 K.