Creep of (La0.55Sr0.45)0.99Mn1−yGayO3

Abstract

Steady-state compressive creep was measured in (La_0.55Sr_0.45)_0.99Mn_1−yGa_yO₃ at temperatures from 1200 to 1270 °C in air at stresses (σ) from 13 to 40 MPa. The Ga concentration was y = 0, 0.05, and 0.10. Strains to 0.14 were obtained. In the creep equation for strain rate,  = Aⁿ exp(−Q/RT), stress exponents (n) were between 1.3 and 1.7, indicating that diffusional flow is the dominant creep mechanism, and the activation energy (Q) was found to vary from 355 kJ mol⁻¹ for y = 0 to 485 kJ mol⁻¹ for y = 0.10.