Abstract
The oxidation behavior of pure chromium was observed in a transmission electron microscope while the specimens were heated by means of a hot stage. It was found that the morphology of chromium oxides was quite different at two different temperatures of 540 and 700°C. In the former case, the oxide grew mainly in a columnar form having a crystallographic relationship with the matrix chromium. In the latter, it grew in random orientations. The columnar oxide at the lower temperature was oriented with its (1\bar10) plane parallel to a (1\bar10) plane of the matrix. It was suggested from the analysis that a considerable amount of strain was present at the interface between the columnar oxide and the matrix chromium. In addition, the oxide was found to grow most easily on {100} planes of the chromium matrix.
