ON THE INFLUENCE OF TEMPERATURE ON THE SUBGRAIN SIZE

In the alloy Fe-3wt.% Si, the influence of temperature on the deformat ion substructure formed in creep at 823-973 K has been investigated. T he overall 'athermal' relation combining data obtained at different te sting temperatures was splitted to several 'isothermal' relations whos e parameters can be correlated with temperature. A detailed investigat ion by optical and electron microscopy and the image analysis of micro structures in specimens deformed at different temperatures at the same applied stress confirm the decrease of the subgrain size with increas ing temperature but did not reveal any pronounced change of the subgra in shape. The effect of temperature on the subgrain size is discussed as a real effect and as an artefact effect which might be due to a tem perature dependence of the pitting process. (C) 1998 Elsevier Science S.A. All rights reserved.