Microstructural comparison of effects of hafnium and titanium additions in spark-plasma-sintered Fe-based oxide-dispersion strengthened alloys

Microstructural and mechanical characterisation of Fe-14Cr-0.22Hf alloy fabricated by spark plasma sintering

“…% concentration of Hf in the alloy was selected to produce a final oxide fraction comparable with the 0.25Y 2 O 3 (wt. %) content in ODS alloys previously prepared and characterised by authors of the current work [28,36]. Addition of Hf to steel alloys already containing Y 2 O 3 has been shown to promote the formation of finer oxides with respect to the original ODS alloy [37].…”

“…TEM was conducted in a JEOL 2100 equipped with STEM-EDS operating at 200 kV and in a JEOL 3000F operating at 300 kV. Samples suitable for TEM observation were prepared by the FIB lift-out technique combined with flash-polishing [36].…”

“…The temperature used in the SPS process was 0.76T m [41] of the Fe-14Cr alloy, where the growth of larger grains might be expected, so the presence of Hf may have conferred thermal stability to the microstructure. For comparison, two alloys with nominal composition Fe-14Cr-0.4Ti-0.25Y 2 O 3 (wt.%) and Fe-14Cr-0.25Y 2 O 3 -0.22Hf (wt.%), mechanically alloyed and SPSconsolidated under the same conditions, showed grain sizes up to 15 m [28,36]…”

Irradiation hardening induced by blistering in tungsten due to low-energy high flux hydrogen plasma exposure

“…Previous literatures have shown that the depth of damage introduced by the Xe + plasma FIB created 20~40% less damage than that created by a Ga + FIB [26,27]. A final flash electro-polishing procedure [28] was used to remove the beam damaged layer induced by plasma FIB on both sides of the lamellae at 14 V in 0.5 w.t.% NaOH aqueous at 273 K for 4 ms. The TEM microstructural characterization was carried out on an FEI Talos F200 at 200 keV.…”

Removal of FIB Damage using Flash Electropolishing for Artifact-free TEM Foils

“…This demonstrated a need to find a different approach that can consistently remove the artificial defects produced by FIB milling. We followed the flash electropolishing approach first reported by Huang et al [3], and report here our success in utilizing flash electropolishing to produce FIB lamella from HT-9 that are completely free of both the small "black spot" damage and FIB milling induced dislocation loops, as well as the restructured sample surface. Figure 1 shows the simple setup of the flash electropolishing apparatus developed in house.…”