On the Role of Alloy Composition and Sintering Parameters in the Bimodal Grain Size Distribution and Mechanical Properties of ODS Ferritic Steels Articles uri icon

publication date

  • November 2016

start page

  • 5325

end page

  • 5333

issue

  • 11

volume

  • 47A

International Standard Serial Number (ISSN)

  • 1073-5623

Electronic International Standard Serial Number (EISSN)

  • 1543-1940

abstract

  • A sintered 14Cr-5Al-3W oxide dispersion strengthened steel was produced by mechanical alloying and consolidated by field-assisted hot pressing. First, a nanostructured powder was developed thanks to the high-energy milling used for introducing 0.4Ti-0.25Y(2)O(3)-0.6ZrO(2) into the prealloyed Fe-Cr-Al-W powder, and then the processed powders were consolidated under a low diffusive technique to better retain the microstructure inherited from milling. The effect of the addition of zirconia and of the pressure applied during sintering on the final bimodal grain microstructure and mechanical properties is assessed. Both parameters are responsible for the refinement of the microstructure by increasing the volume fraction of the ultrafine grains (0 to 400 nm), leading to an enhancement of the mechanical properties, such as the microhardness and tensile strength.

keywords

  • thermal-stability; impact properties; iron-powder; zr addition; microstructure; zirconium; ductility; behavior; metals; nanocrystalline