Malki Pinkas, Zvi Foxman, Nataly Academic Article uri icon

abstract

  • The sensitivity of thermo-electric power (TEP) measurement to detect the undesired a–a0 phase separation occurring in Cr-rich oxide dispersion strengthened steels was investigated. TEP values were found to increase with time of exposure to 475 C—the maximum temperature of the miscibility gap in Fe–Cr alloys. Exposure to 650 C did not induce any changes in the TEP value. By examining the bend contours in dark-field TEM images, a0 precipitates were evidenced in aged PM2000. Using the Fe–XCr–YAl model alloys and X-ray photoelectron spectroscopy, the changes in TEP were traced back to the depletion of Cr from the matrix, caused by the formation of the Cr-rich a0 phase. By quantifying the effect of Cr content on the TEP value of model alloys, it was estimated that following 1000 h of aging, the Cr concentration in the a matrix of PM2000 alloy was …

publication date

  • January 1, 2015