TY - JOUR

T1 - Atomic resolution imaging of precipitate transformation from cubic TaN to tetragonal CrTaN

A1 - Danielsen,Hilmar Kjartansson

A1 - Hald,John

A1 - Somers,Marcel A. J.

AU - Danielsen,Hilmar Kjartansson

AU - Hald,John

AU - Somers,Marcel A. J.

PB - Pergamon

PY - 2012

Y1 - 2012

N2 - In 9–12% Cr creep-resistant steels Cr(V,Nb,Ta)N Z-phase is known to replace metastable (V,Nb,Ta)N MN precipitates at high temperatures. The precipitation process of Z-phase does not follow the classical nucleation theory, where dissolving MN particles provide constituents for Z-phase nucleation in the matrix. Using atomic resolution transmission electron microscopy, the current work demonstrates that metastable cubic TaN precipitates in a complex steel gradually transform compositionally and crystallographically into stable tetragonal CrTaN precipitates under the influence of Cr indiffusion from the steel matrix.

AB - In 9–12% Cr creep-resistant steels Cr(V,Nb,Ta)N Z-phase is known to replace metastable (V,Nb,Ta)N MN precipitates at high temperatures. The precipitation process of Z-phase does not follow the classical nucleation theory, where dissolving MN particles provide constituents for Z-phase nucleation in the matrix. Using atomic resolution transmission electron microscopy, the current work demonstrates that metastable cubic TaN precipitates in a complex steel gradually transform compositionally and crystallographically into stable tetragonal CrTaN precipitates under the influence of Cr indiffusion from the steel matrix.

KW - Heat-resistant steels

KW - Nitrides

KW - High-resolution electron microscopy (HREM)

KW - Crystal structure

KW - Phase transformations

U2 - 10.1016/j.scriptamat.2011.11.005

DO - 10.1016/j.scriptamat.2011.11.005

JO - Scripta Materialia

JF - Scripta Materialia

SN - 1359-6462

IS - 5

VL - 66

SP - 261

EP - 264

ER -