Discussion of the complex thermo-mechanical behavior of Ba0.5Sr0.5CO0.8Fe0.2O3-δ

摘要: Abstract The measurement of the thermo-mechanical properties cubic Ba 0.5 Sr Co 0.8 Fe 0.2 O 3− δ (BSCF) with ring-on-ring test and depth-sensitive micro-indentation testing revealed an anomaly between 200 °C 400 °C. In particular, stiffness decreases strongly room temperature (RT) 200 °C, subsequently increases again to a stable value at ∼300 °C. Fracture stress toughness show qualitatively similar behavior. fracture up 400 °C, before recovering 500 °C 800 °C. XRD verified that BSCF remains in relevant range. Hence anomalies are attributed transition 3+ spin states, which is experimentally confirmed by susceptibility measurements. surfaces specimens were not affected RT 700 °C, only purely transgranular mode was observed.