Determination of retained austenite using an X-ray texture goniometer

A new X-ray technique has been developed for determining the amount of retained austenite in steels with preferred orientation, such as white cast irons and deformed steels. The technique uses an X-ray texture goniometer. The X-ray goniometer was run as if a texture was being determined, but the raw data were collected via a special program. From analysis of the raw data for several austenite and martensite reflections, a very accurate value for the retained austenite content was obtained. The technique has been evaluated using a textured specimen with a known amount of retained austenite, and by carrying out the determination at different orientations of a single specimen. Compared with other methods, this technique can produce retained austenite values to an accuracy of ±1.5%. As an application of this technique, the relationship between the amount of retained austenite and heat-treatment parameters in a white cast iron has been studied.