The automotive industry has focused on the development of metallic materials with high specific strength, which can meet both fuel economy and safety goals. Here, a new class of ultrafine-grained high-Mn steels containing nano-scale oxides is developed using powder metallurgy. First, high-energy mechanical milling is performed to dissolve alloying elements in Fe and reduce the grain size to the nanometer regime. Second, the ball-milled powder is consolidated using spark plasma sintering. During spark plasma sintering, nanoscale manganese oxides are generated in Fe-15Mn steels, while other nanoscale oxides (e.g., aluminum, silicon, titanium) are produced in Fe-15Mn-3Al-3Si and Fe-15Mn-3Ti steels. Finally, the phases and resulting hardness of a variety of high-Mn steels are compared. As a result, the sintered pallets exhibit superior hardness when elements with higher oxygen affinity are added; these elements attract oxygen from Mn and form nanoscale oxides that can greatly improve the strength of high-Mn steels.

Abstract
1. 서 론
2. 실험방법
3. 실험결과 및 고찰
4. 결 론
References

• 전종규(국민대학교 신소재공학부) | Jonggyu Jeon (School of Materials Science and Engineering, Kookmin University)
• 김정준(국민대학교 신소재공학부) | Jungjoon Kim (School of Materials Science and Engineering, Kookmin University)
• 최현주(국민대학교 신소재공학부) | Hyunjoo Choi (School of Materials Science and Engineering, Kookmin University) Corresponding Author