The influence of platinum on the maintenance of α-Al 2 O 3 as a protective scale

摘要: The influence of externally located platinum on the isothermal stability α-Al2O3 scales formed at high temperatures has been examined. It observed that a nickel-base alloy forms an external scale during oxidation 1200°C, but this breaks down isothermally, enabling faster-growing Cr2O3-rich to develop. However, in presence metal alongside specimen furnace hot zone, breakdown is postponed for substantial period time. appears platinum, as volatile species PtO2, incorporated into growing where it either influences stress relief mechanism temperature or reduces growth generation and thus significantly enhances scale.