Tailoring the microstructure and the mechanical properties of ultrafine grained high strength ferritic steels by powder metallurgy

JOURNAL OF NUCLEAR MATERIALS

卷:465

Article

Mouawad, B.¹  Boulnat, X.^1,2  Fabregue, D.¹  Perez, M.¹  de Carlan, Y.² 

[1] Univ Lyon, INSA Lyon, MATEIS UMR CNRS 5510, F-69621 Villeurbanne, France

[2] CEA Saclay, DEN, Serv Rech Met, F-91191 Gif Sur Yvette, France

关键词: ODS steel;    Powder metallurgy;    Ultrafine grained steel;    EBSD;    Yield strength model;   

DOI  :  10.1016/j.jnucmat.2015.05.053

来源: Elsevier

【 摘 要 】

Three model powder materials (i) atomized, (ii) atomized + milled, and, (iii) atomized + milled + alloyed with yttria (Y2O3) and titanium were consolidated within Spark Plasma Sintering device at 850, 950 and 1050 degrees C. Depending on the materials, nanostructured, or even bimodal grain size distribution can be observed. These structures lead to a wide range of mechanical behavior: the tensile strength at room temperature can be tailored from 500 to 1200 MPa with total elongation from 8 to 35%. The bimodal grain size distribution is believed to provide both good yield stress and ductility. Finally, a yield stress model based on the effect of solute atoms, dislocations, grains boundaries and precipitates is presented and it permits to predict accurately the experimental values for all specimens and conditions. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

Free