STP306: Water-Vapor Corrosion of Beryllia

    Browne, CC
    Senior Engineer, Aircraft Nuclear Propulsion Division, General Electric Co., Cincinnati, Ohio

    Pages: 8    Published: Jan 1962


    Abstract

    Fundamental investigations of the reaction of water vapor with beryllia at high temperatures and under conditions of equilibrium between the gas phase and solid beryllia reveal that at a given temperature and gas flow the rate of water-vapor attack varies directly with the partial pressure of water vapor. The equilibrium partial pressure of the corrosion product varies with temperature according to this equation: log Pmm = 4.584 − 9060 / T°K

    For turbulent flow of moist air over hot beryllia surfaces the beryllia loss rates may be calculated and are less than would be expected for saturation of the bulk air stream with corrosion product. Coating of the beryllia surface with an oxide which is not attacked at high temperatures appears to be the most effective way of eliminating beryllia loss in moist atmospheres.


    Paper ID: STP44392S

    Committee/Subcommittee: E10.02

    DOI: 10.1520/STP44392S


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