This study investigates the effect of thermo-mechanical treatment on the damping capacity of the Fe-20Mn-12Cr- 3Ni-3Si alloy with deformation induced martensite transformation. Dislocation, αʹ and ε-martensite are formed, and the grain size is refined by deformation and thermo-mechanical treatment. With an increasing number cycles in the thermo-mechanical treatment, the volume fraction of ε-martensite increases and then decreases, whereas dislocation and α'-martensite increases, and the grain size is refined. In thermo-mechanical treated specimens with five cycles, more than 10 % of the volume fraction of ε-martensite and less than 3 % of the volume fraction of αʹ-martensite are attained. Damping capacity decreases by thermomechanical treatment and with an increasing number of cycles of thermo-mechanical treatment, and this result shows an opposite tendency for general metal with deformation induced martensite transformation. The damping capacity of the thermomechanical treated damping alloy with deformation induced martensite transformation greatly affect the formation of dislocation, grain refining and α'-martensite and then ε-martensite formation by thermo-mechanical treatment.

Abstracts
 1. 서 론
 2. 실험방법
  2.1 시료
  2.2 가공열처리
  2.3 미세조직의 관찰
  2.4 감쇠능 측정
 3. 실험결과 및 고찰
  3.1 미세조직
  3.2 가공열처리에 따른 미세조직변화
  3.3 감쇠능에 미치는 가공열처리의 영향
 4. 결 론
 References

• 한현성(한국폴리텍대학 대구캠퍼스 산업설비학과) | Hyun-Sung Han (Dep. of Automatic Facilities, Korea Polytechnics College Daegu Campus)
• 강창룡(부경대학교 금속공학과) | Chang-Yong Kang (Dept. of Metallurgical Engineering, Pukyong National University) Corresponding author