Manufacturing and characterization of Ni-free N-containing ODS austenitic alloy
Abstract
Ni-free N-containing oxide dispersion strengthened (ODS) austenitic alloys were manufactured by mechanical alloying (MA) followed by spark plasma sintering (SPS). The phase evolutions during milling under a nitrogen atmosphere and after sintering were studied by X-ray diffraction (XRD). Transmission electron microcopy (TEM) and alloy contrast variation analysis (ACV), including small-angle neutron scattering (SANS) and ultra-small-angle X-ray scattering (USAXS), revealed the existence of nanoparticles with a diameter of 3-51 nm for the samples sintered at 950 °C. Sintering at 1000 °C for 5 and 15 min caused slight growth and a significant coarsening of the nanoparticles, up to 70 nm and 128 nm, respectively. The ACV analysis indicated the existence of two populations of Y2O3, ɛ-martensite and MnO. The dispersive X-ray spectrometry (EDS) confirmed two kinds of nanoparticles, Y2O3 and MnO. The material was characterized by superior micro-hardness, of above 500 HV0.1.
- Publication:
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Journal of Nuclear Materials
- Pub Date:
- April 2018
- DOI:
- 10.1016/j.jnucmat.2018.01.025
- Bibcode:
- 2018JNuM..501...72M
- Keywords:
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- ODS austenitic steel;
- Mechanical alloying;
- Spark plasma sintering (SPS);
- Nanoparticle;
- Small-angle neutron scattering (SANS);
- Contrast variation analysis (ACV)