Strain-induced Z-phase formation in a 9% Cr-3% Co martensitic steel during creep at elevated temperature

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:724

Article

Fedoseeva, A.¹  Nikitin, I¹  Dudova, N.¹  Kaibyshev, R.¹ 

[1] Belgorod Natl Res Univ, Pobeda 85, Belgorod 308015, Russia

关键词: Steel;    Electron microscopy;    Precipitation;    Phase transformation;    Orientation relationships;   

DOI  :  10.1016/j.msea.2018.03.081

来源: Elsevier

【 摘 要 】

The size and distribution of Cr(V,Nb)N (Z-phase) particles in a 9Cr-3Co-2W-0.6Mo-0.1Ni-0.2V-0.06Nb-0.1C0.05N-0.005B steel subjected to creep rupture test during 11,151 h at 650 'C under an applied stress of 100 MPa were studied. The replacement of V-rich (V,Nb)(C,N) carbonitrides by Z-phase was accelerated by plastic flow as suggested by a comparative analysis of these particles in different portions of crept specimen, namely, the grip section, the portion of uniform elongation, and the necked portions. Coarse ybridZ-phase particles evolved throughout the crept specimen by an in situ transformation mechanism. The strain-induced Z-phase nucleated on the V-rich (V,Nb)(C,N)/ferrite interfaces, leading to the formation of numerous Z-phase particles with dimensions less than 50 nm in the necked portion.

【 授权许可】

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