| 摘要 |
Conventional methods of examining chromium-containing nickel-based alloys, such as Inconel 600 alloy, for chromium-deficient phases necessitate surface corrosion or cutting and hence are methods accompanied by destruction and contrary to the idea of nondestructive examination. The information obtainab le with the methods has been limited to one concerning surface chromium-deficie nt phases. The method, which is for examining a chromium-containing nickel-base d alloy for grain boundary corrosion based on thermal sensitization, comprises : measuring the saturation magnetization Ms(Ti) of a test piece at each of temperatures distributed at the same interval throughout the range of from t he minimum to the maximum Curie temperatures corresponding to the chromium concentrations in the chromium-deficient phase of the alloy; and quantitatively determining the average spatial distribution of the chromium- deficient phase of the test piece, i.e., the volumes for respective chromium concentrations of the chromium-deficient phase at around grain boundaries, using a given arithmetic expression.
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