Grain Growth and Precipitation Behavior of Iridium Alloy DOP-26 During Long Term Aging

Abstract

The influence of long term aging on grain growth and precipitate sizes and spatial distribution in iridium alloy DOP-26 was studied. Samples of DOP-26 were fabricated using the “new process,” recrystallized for 1 hour (h) at 1375 °C, then aged at either 1300, 1400, or 1500 °C for times ranging from 50 to 10,000 h. Grain size measurements (vertical and horizontal mean linear intercept and horizontal and vertical projection) and analyses of iridium-thorium precipitates (size and spacing) were made on the longitudinal, transverse, and rolling surfaces of the as-recrystallized and aged specimens from which the two-dimensional spatial distribution and mean sizes of the precipitates were obtained. The results obtained from this study are intended to provide input to grain growth models.