Effect of oxygen partial pressure on grain-boundary transport in alumina
Source abstract
Abstract
Abstract The oxidation of the bond coat in a thermal barrier coating results in the formation of a protective alumina scale. Such scales experience large gradients in oxygen partial pressure ( P O 2 ) during formation, but it is unclear how P O 2 affects grain-boundary (GB) transport in alumina. To study the effect of P O 2 on GB kinetics in alumina, the rate of oxygen penetration was measured at 1400 °C over a wide range of P O 2 . This was accomplished using a novel reduction experiment using nickel aluminate spinel particles. The results indicated that the dependence of the boundary transport on P O 2 is mainly due to the driving force, namely the gradient in P O 2 across the alumina. Point-defect models were then invoked to interpret the measurements, and it was found that transport in an alumina scale is controlled by extrinsic defects.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: High-Temperature Coating Behaviors · Advanced ceramic materials synthesis · Semiconductor materials and devices
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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