| Abstract |
A number of candidate turbine materials are being evaluated for their resistance to erosion, corrosion, and stress corrosion cracking (SCC) in geothermal brines. These materials include Fe-, Ni-, Co- and Ti-base alloys, coating and ceramics. Tapered wearblades, simulating the leading edge of a turbine blade, are exposed to the direct impact of a two phase nozzle exhaust. Bent beam SCC specimens, which are constrained in fixtures attached to the wearblade holders, are also exposed to this exhaust. We describe the results of a test series in which acidified liquid brine was expanded to atmospheric pressure. The tests were performed at the LLL Field Test Station near Niland in the Salton Sea Geothermal Field. Evaluation of the exposed materials indicates that Ti-base alloys show the most promise for turbine wheel components in the high salinity geothermal environments. |