Skip to main content
placeholder image

Precipitation behavior of type 347H heat-resistant austenitic steel during long-term higherature aging

Journal Article


Abstract


  • The microstructural evolution of type 347H heat-resistant austenitic steel during long-term aging at 700-900 ��C was investigated by using a transmission microscope, a scanning electron microscope, and electron energy spectrum technology. The microstructural examination showed the typical micrographs of MX carbonitrides and M23C6 carbides after aging. The existence of the Z phase (NbCrN) at the grain boundaries during aging was identified. Meanwhile, the possible precipitation sequence of these particles was also confirmed. In the beginning of aging, fine Nb(C,N) precipitates first, then, M23C6 carbides precipitate along the grain boundaries. Finally, the Z phase is also observed at the grain boundaries. Moreover, the influence of isothermal holding temperature on the precipitation of MX carbonitrides and M23C6 carbides was discussed. The various microstructural characterizations showed that the M23C6 carbides and MX carbonitrides precipitate more easily with the increase of aging temperature. Furthermore, the number and the size of MX particles and M23C6 carbides increase when the isothermal holding time is prolonged.

Publication Date


  • 2015

Citation


  • Zhou, Y., Li, Y., Liu, Y., Guo, Q., Liu, C., Yu, L., . . . Li, H. (2015). Precipitation behavior of type 347H heat-resistant austenitic steel during long-term higherature aging. Journal of Materials Research, 30(23), 3642-3652. doi:10.1557/jmr.2015.343

Scopus Eid


  • 2-s2.0-84946763526

Start Page


  • 3642

End Page


  • 3652

Volume


  • 30

Issue


  • 23

Place Of Publication


Abstract


  • The microstructural evolution of type 347H heat-resistant austenitic steel during long-term aging at 700-900 ��C was investigated by using a transmission microscope, a scanning electron microscope, and electron energy spectrum technology. The microstructural examination showed the typical micrographs of MX carbonitrides and M23C6 carbides after aging. The existence of the Z phase (NbCrN) at the grain boundaries during aging was identified. Meanwhile, the possible precipitation sequence of these particles was also confirmed. In the beginning of aging, fine Nb(C,N) precipitates first, then, M23C6 carbides precipitate along the grain boundaries. Finally, the Z phase is also observed at the grain boundaries. Moreover, the influence of isothermal holding temperature on the precipitation of MX carbonitrides and M23C6 carbides was discussed. The various microstructural characterizations showed that the M23C6 carbides and MX carbonitrides precipitate more easily with the increase of aging temperature. Furthermore, the number and the size of MX particles and M23C6 carbides increase when the isothermal holding time is prolonged.

Publication Date


  • 2015

Citation


  • Zhou, Y., Li, Y., Liu, Y., Guo, Q., Liu, C., Yu, L., . . . Li, H. (2015). Precipitation behavior of type 347H heat-resistant austenitic steel during long-term higherature aging. Journal of Materials Research, 30(23), 3642-3652. doi:10.1557/jmr.2015.343

Scopus Eid


  • 2-s2.0-84946763526

Start Page


  • 3642

End Page


  • 3652

Volume


  • 30

Issue


  • 23

Place Of Publication