High-temperature corrosion specimen preparation

It is hardly surprising that the preparation of surfaces of plain specimens for stress-corrosion tests can sometimes exert a marked influence upon results. Heat treatments carried out on specimens after their preparation is otherwise completed can produce barely perceptible changes in surface composition, e.g. decarburisation of steels or dezincification of brasses, that promote quite dramatic changes in stress-corrosion resistance. Similarly, oxide films, especially if formed at high temperatures during heat treatment or working, may influence results, especially through their effects upon the corrosion potential. 

Focus here is on service tests that evaluate materials in applications that involve both high-temperature and corrosive conditions. B lsic chemical, thermodynamic, and physical principles are discussed. Specimen preparation, environment synthesis and evaluation are briefly reviewed and, where appropriate, reference is made to more detailed information and studies available in the technical literature. 

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