Abstracts Book - IMRC 2018

• SE2-P015
FABRICATION AND CHARACTERIZATION OF OXIDE DISPERSION
STREGNTHENED ALLOYS USING 3D PRE-FORMING PROCESS FOR
THE ADDITIVE MANUFACTURING
Sanghoon Noh 1 , Suk Hoon Kang 1
1 Korea Atomic Energy Research Institute, Nuclear Materials Division, Korea.
Oxide dispersion strengthened (ODS) alloy is being considered as an in-core
structural material for next-generation nuclear systems because of its excellent
high strength and irradiation resistances. In many ODS alloys, finely dispersed
nano-oxide particles with a high number density in the homogeneous grains can
be very attractive to achieve superior mechanical properties at high
temperatures, and these favorable microstructures can be significantly changed
using fabrication process parameters during the mechanical milling of alloying
powders. In present days, many additive manufacturing processes are being
developed for heat-resistant components in fossil power, defense, aerospace
and so on. Using the additive manufacturing process, complicated shape
components with ODS alloy powders can be fabricated and it will be very
prospective process for high temperature service applications. For preliminary
study, mechanical alloying and sintering behaviors of 15Cr-1Mo ODS alloys were
investigated. Raw powders and Y2O3 powder were mechanically milled for
various milling times using a high energy horizontal ball-mill apparatus. Powder
properties such as the surface morphology, size distribution, and crystallite size
were evaluated. To simulate the pre-forming process, the ODS alloy powders
were mechanically mixed with organic material powder. A high vacuum furnace
was then employed to fabricate the alloys. As increase the milling time, the
distribution of ferritic grains with fine oxide particles was considerably
homogenized. However, excessive milling led to abnormal grain growth by the
impurity contamination. Surface morphology of mechanically alloyed powders
was quite rough with an irregular shape and this should be solved for the
additive manufacturing process.
Keywords: ODS alloy, pre-forming, additive manufacturing
Presenting authors email: shnoh@kaeri.re.kr