Gas turbine and advanced HTGR materials screening test program: 10,000-hour results and semiannual progress report for the period ending March 31, 1977

Work on the Gas-Turbine and Advanced High-Temperature Gas-Cooled Reactor (HTGR) Materials Screening Test Program is documented. Emphasis is on the results and analyses of creep data to 11,000 hr and the detailed metallurgical evaluations performed on candidate alloy specimens tested for up to 10,000 hr. Long-term creep and unstressed aging data in controlled-impurity helium and in air at 650, 800, and 9000C are reported for the original alloys in the program, including the vacuum-cast Ni-base superalloys, IN 100, Rene 100, IN 713, MM 004, M 21, and IN 738; the wrought solid-solution-strengthened Ni--Cr alloys, Hastelloy X and Inconel 617; the centrifugally-cast austenitic Fe--Ni--Cr alloy, IN 519; the oxide-dispersion-strengthened (ODS) Ni--Cr alloys, MA 753 and MA 754; and the wrought Mo-base alloy, MoTZM. Results at 6500C and 10,000 hr for the precipitation-strengthened alloys Inconel 718, Inconel 706, and A 286 are also included. Similar, but much shorter term data at 800, 900, and 10000C for the recently added wrought alloys Hastelloy X (second heat), Hastelloy S, RA 333, and HD 556, and the additional centrifugally-cast alloys HK 40, Supertherm, Manaurite 36X, Manaurige 36XS, and Manaurite 900, are also reported