High-temperature, Low-cycle Fatigue Data of Advanced Copper-base Alloys for Rocket Nozzles

Résumé du livre

Short-term tensile and low-cycle fatigue data are reported for five advanced copper-base alloys: Sputtered Zr-Cu as- received, sputtered Zr-Cu heat-treated, Glidcop AL-10, and NASA alloys 1-1A and 1-1B. Tensile tests were performed in argon at 538°C using an axial strain rate of 2 x 10−3 sec−1. Yield strength and ultimate tensile strength data are reported along with reduction in area values. Axial strain controlled low-cycle fatigue tests were performed in argon at 538°C using an axial strain rate of 2 x 10−3 sec−1 to define the fatigue life over the range from 100 to 3000 cycles for the five materials studied. It was found that the fatigue characteristics of the NASA 1-1A and NASA 1-1B compositions are essentially identical and represent fatigue life values which are much greater than those for any of the other materials tested. In a more extensive evaluation of the NASA 1-1B alloy the effect of temperature at a strain rate of 2 x 10−3 sec−1 was evaluated along with the effect of strain rates o 4 x 10−4 and 1 x 10−2 sec−1 at 538°X. Hold-time data are also reported for the NASA 1-1B alloy at 538° using 5 minute hold periods in tension only and compression only at two different strain range values. Hold periods in tension were shown to be much more detrimental than hold periods in compression.