| Popis: |
The dislocation arrangements in 304 stainless steel and Incoloy 800 have been determined as a function of temperature and strain. Dislocation pile-ups were observed in both alloys in spite of the fact that the stacking fault energies were considerably different, viz. 30 erg/cm2 for the Incoloy 800. The stress-corrosion behaviour of the two alloys in magnesium chloride boiling at 142°C was determined. The Incoloy 800 was found to be considerably more resistant than the 304 stainless steel. After critically reviewing the current theories of stress corrosion and structural and stress-corrosion data for a series of austenitic alloys, it was concluded that the data could best be correlated with the theory proposed by Swann. According to this theory, the presence of short range order is expected to markedly influence dislocation arrangement and stress-corrosion behaviour. A review of the literature revealed that there is some indirect evidence to indicate the presence of short range order in certain of the austenitic alloys, but the evidence is not conclusive. |
