AbstractSamples of austenitic stainless steels from various sources have been thermally cycled. Many materials exhibited a volume expansion on cooling superimposed on the normal thermal contraction, as a result of an austenite → ferrite phase transformation. Samples of materials which exhibited the ferrite transformation also show a period of rapid oxidation on re‐exposure after cooling during the first autoclave shutdown of an oxidation test. It is proposed that the local volume expansion accompanying the formation of ferrite on cooling disrupts the initial protective oxide scale thereby allowing oxidation to proceed more rapi
展开▼