Mechanical Alloying and Powder Forging of 18%Cr Oxide Dispersion-Strengthened Steel Produced Using Elemental Powders

Journal Article · Tue Jan 15 04:00:00 EST 2019 · Journal of Materials Engineering and Performance

DOI:https://doi.org/10.1007/S11665-018-3801-0· OSTI ID:22971019

Kumar, D.; Dabhade, V. V. ^[1]; Laha, K.; Sakthivel, T. ^[2]

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1. Indian Institute of Technology (IIT), Department of Metallurgical and Materials Engineering (India)
2. Indira Gandhi Centre for Atomic Research (IGCAR), Mechanical Metallurgy Group (India)

Oxide dispersion-strengthened (ODS) ferritic steels are potential materials for cladding tubes in fast breeder fission reactors. These are mostly prepared by mechanical alloying of yttria powder with pre-alloyed powders. Using elemental powders offers flexibility in the choice of alloy compositions. Here we report mechanical alloying of Fe-18Cr-2W-0.2Ti-0.35Y{sub 2}O{sub 3} (compositions in wt.%) ODS steel using elemental powders of Fe, Cr, W and Ti with yttria powder. After 5 h of milling, no significant changes in particle size and crystallite size were observed. Powders milled for 5 and 7 h were consolidated through powder forging route. The optimum milling time for mechanical alloying could be determined only after evaluating the forgings. It is difficult to achieve recrystallization in ODS alloys. The forging process parameters were optimized to achieve a dense alloy with a fine recrystallized microstructure. Factors leading to recrystallization are discussed. It is shown that recrystallization in ODS steels is more likely to occur during forging as compared to extrusion/rolling. The powder forging route offers several advantages over the conventional extrusion or HIP routes.

• OSTI ID: 22971019
• Journal Information: Journal of Materials Engineering and Performance, Journal Name: Journal of Materials Engineering and Performance Journal Issue: 1 Vol. 28; ISSN 1059-9495; ISSN JMEPEG
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
FAST FISSION
FERRITIC STEELS
FLEXIBILITY
FORGING
IRON
PARTICLE SIZE
POWDER METALLURGY
RECRYSTALLIZATION
TUNGSTEN ALLOYS
YTTRIUM OXIDES