TY - GEN A1 - Schumacher, Gerhard A1 - Klingelhöffer, Hellmuth A1 - Rehfeldt, T. T1 - Changes in lattice structure and microhardness during thermal treatment of a NiCoCrAIY alloy T2 - Thermal barrier coatings - 2000 N2 - The stability of microstructure and the microhardness of a NiCoCrAlY alloy was studied after thermal treatment at high temperatures and subsequent quenching into ice water. The alloy revealed mainly two ordered phases, a gamma' phase with L12 lattice structure and a beta phase with B2 structure. The gamma' phase is shown to become unstable in the temperature range between 1073 K and 1373 K where it undergoes an order-disorder phase transformation. The low transformation temperature compared to pure Ni3Al is ascribed to deviations from the Ni3Al stoichiometry and to the additional alloying elements Co and Cr. The gamma'-gamma order-disorder transformation is shown to be attended by a decrease in microhardness of about 30 %. T2 - Symposium M: Thermal Barrier Coatings; MRS (Materials Research Society) fall meeting CY - Boston, MA, USA DA - 2000-01-01 PY - 2000 SN - 0272-9172 N1 - Serientitel: Materials Research Society symposium proceedings – Series title: Materials Research Society symposium proceedings IS - 645 PB - Materials Research Society CY - Warrendale, Pa. AN - OPUS4-1052 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -