Nitrogen impurity gettering in oxide dispersion ductilized chromium Academic Article uri icon


  • Work by Scruggs in the 1960s demonstrated that tensile ductility could be achieved at room temperature in powder metallurgically-produced Cr alloyed with MgO. During consolidation, much of the MgO converted to the MgCr2O4 spinel phase, which was hypothesized to getter nitrogen from the Cr, rendering it ductile. We have duplicated this effect, achieving room temperature tensile elongations of 4% for hot-pressed Cr-6MgO-(0-1)Ti (wt.%) and 10% for hot-pressed and extruded Cr-6MgO-0.75Ti. Direct incorporation of nitrogen into the MgCr2O4 phase was not detected; however, impurities, particularly nitrogen and sulfur, were observed to segregate to and/or precipitate at interfaces between the MgO/MgCr2O4 phases and the Cr matrix. Exploratory studies of other non-spinel forming oxide dispersions (La2O3, TiO2 and Y2O3) showed a similar pattern of impurity segregation/precipitation, suggesting that there is nothing unique about spinel dispersions in Cr with regards to impurities. However, none of these other dispersions resulted in similar levels of tensile elongation. 2003 Elsevier Science B.V. All rights reserved.

published proceedings

  • Materials Science and Engineering A

author list (cited authors)

  • Brady, M. P., Anderson, I. M., Weaver, M. L., Meyer, H. M., Walker, L. R., Miller, M. K., ... Walls, C. A.

citation count

  • 13

complete list of authors

  • Brady, MP||Anderson, IM||Weaver, ML||Meyer, HM||Walker, LR||Miller, MK||Larson, DJ||Wright, IG||Sikka, VK||Rar, A||Pharr, GM||Keiser, JR||Walls, CA

publication date

  • October 2003