비파괴검사학회지 (Journal of the Korean Society for Nondestructive Testing)

  • 제36권5호
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  • Pages.377-383
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  • 2016
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  • 1225-7842(pISSN)
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  • 2287-402X(eISSN)
한국비파괴검사학회 (The Korean Society for Nondestructive Testing)
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페라이트기 11Cr 저탄소강의 자기적 특성에 대한 고온 장시간 시효열화 효과

Effect of Long-Term Aging Degradation on Magnetic Properties of Ferritic 11Cr Low-Carbon Steel

  • 투고 : 2016.09.07
  • 심사 : 2016.10.18
  • 발행 : 2016.10.30
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초록

페라이트기 11Cr 저탄소강의 자기적 특성에 대한 고온 장시간 시효열화의 영향에 대해서 연구하였다. 장시간 시효시간이 증가함에 따라서 자기이력곡선으로부터 구한 보자력, 자기이력손실은 감소하였고 이들은 시효시간에 대해 2차 지수함수 관계를 나타내었다. 비커스 경도 역시 시효시간의 증가에 따라서 감소하여 기계적 물성의 연화를 나타내었다. 미세조직적 분석으로 주사전자현미경, 후방산란전자 및 X-선 회절시험을 수행하였다. 입계에서는 $Cr_{23}C_6$ 석출물의 급격한 성장과 입내의 래스 경계부에서 Laves ($Fe_2W$)상이 발달하였다. 조대한 석출물들로 인해 장시간 시효열화에 따라서 고용원소의 고갈과 래스 하부조직이 소멸되었다. 이는 자기적 물성과 기계적 물성의 연화현상과 밀접한 관련을 갖게 된다.

The effect of long-term aging degradation on magnetic properties of ferritic 11Cr low-carbon steel was investigated. Coercivity and hysteresis loss measured from the hysteresis loops decreased with long-term aging time and showed that the relation was well fitted by a second order exponential function. Vickers hardness also decreased with aging time and resulted in mechanical softening. In addition, the microstructural evolution was observed by the scanning electron microscopy, backscattered electron image and X-ray diffraction. The $Cr_{23}C_6$ precipitates along grain boundary grew fast and Laves ($Fe_2W$) phase on martensitic lath boundaries in interior grains was developed. The solid solution atoms depleted in matrix and lath subgrains recovered owing to precipitate coarsening with long-term aging degradation. There was a close relation with softening of magnetic and mechanical properties.

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참고문헌

  1. J. He, Z. Cui, F. Chen, Y. Xiao and L. Ruan, "The new ductile fracture criterion for 30Cr2Ni4MoV ultra-super-critical rotor steel at elevated temperatures," Materials & Design, Vol. 52, pp. 547-555 (2013) https://doi.org/10.1016/j.matdes.2013.05.080
  2. F. Chen, Z. Cui, D. Sui and B. Fu, "Recrystallization of 30Cr2Ni4MoV ultra-supercritical rotor steel during hot deformation. Part III: Metadynamic recrystallization," Materials Science and Engineering: A, Vol. 540, No. 1, pp. 46-54 (2012) https://doi.org/10.1016/j.msea.2012.01.061
  3. T. Sundararajan, S. Kuroda, J. Kawakita and S. Seal, "High temperature corrosion of nanoceria coated 9Cr-1Mo ferritic steel in air and steam," Surface and Coatings Technology, Vol. 201, No. 6, pp. 2124-2130 (2006) https://doi.org/10.1016/j.surfcoat.2006.02.007
  4. F. Abe, "Research and development of heat-resistant materials for advanced USC power plants with steam temperatures of 700$^{\circ}$C and above," Engineering, Vol. 1, No. 2, pp. 211-224 (2015) https://doi.org/10.15302/J-ENG-2015031
  5. D. Jiang, H. Xu, B. Deng, M. Li, Z. Xiao and N. Zhang, "Effect of oxygenated treatment on corrosion of the whole steam-water system in supercritical power plant," Applied Thermal Engineering, Vol. 93, pp. 1248-1253 (2016) https://doi.org/10.1016/j.applthermaleng.2015.10.098
  6. B. Raj, B. K Choudhary and R. K S. Raman, "Mechanical properties and non-destructive evaluation of chromium-molybdenum ferritic steels for steam generator application," International Journal of Pressure Vessels and Piping, Vol. 81, No. 6, pp. 521-534 (2004) https://doi.org/10.1016/j.ijpvp.2003.12.010
  7. C. S. Kim, K. S. Ryu, S. H. Nahm and S. S. Lee, "Characterization of the high temperature isothermal aging in USC ferrite steel using reversible permeability," Journal of Korean Magnetic Society, Vol. 19, No. 3, pp. 100-105 (2009) https://doi.org/10.4283/JKMS.2009.19.3.100
  8. C. S. Kim, I. H. Kim, I. K. Park and C. Y. Hyun, "Effect of isothermal aging on magnetic properties in 12Cr steel," Key Engineering Materials, Vol. 326-328, pp. 1201-1204 (2006) https://doi.org/10.4028/www.scientific.net/KEM.326-328.1201
  9. X. Guo, J. Gong, Y. Jiang and D. Rong, "The influence of long-term aging on microstructures and static mechanical properties of P92 steel at room temperature," Materials Science and Engineering: A, Vol. 564, pp. 199-205 (2013) https://doi.org/10.1016/j.msea.2012.10.024
  10. G. C. S. Nunes, P. W. C. Sarvezuk, V. Biondo, M. C. Blanco, M. V. S. Nunes, A. M. H. de Andrade and A. Paesano Jr., "Structural and magnetic characterization of martensitic Maraging-350 steel," Journal of Alloys and Compounds, Vol. 646, pp. 321-325 (2015) https://doi.org/10.1016/j.jallcom.2015.06.008
  11. R. A. Taylor, J. P. Jakubovics, B. Astie and J. Degauque, "Direct observation of the interaction between magnetic domain walls and dislocations in iron," Journal of Magnetism and Magnetic Materials, Vol. 31-34, No. 2, pp. 970-972 (1983) https://doi.org/10.1016/0304-8853(83)90758-8
  12. D. C. Jiles, "The effect of compressive plastic deformation on the magnetic properties of AISI 4130 steels with various microstructures," Journal of Physics D: Appl. Phys., Vol. 21, pp. 1196-1204 (1988) https://doi.org/10.1088/0022-3727/21/7/023
  13. S. P. Hong, K. S. Ryu and C. S. Kim, "Nondestructive characterization for remanent life of advanced ferritic steel by reversible permeability," Journal of the Korean Society for Nondestructive Testing, Vol. 33, No. 2, pp. 181-186 (2013) https://doi.org/10.7779/JKSNT.2013.33.2.181
  14. K. S. Ryu, M. G. Kim, S. H. Nahm and C. S. Kim, "Degradation evaluation of mechanical properties for 12Cr ferrite heat resisting steel by reversible permeability," Journal of the Korean Society for Nondestructive Testing, Vol. 30, No. 5, pp. 464-470 (2010)
  15. T. Nagata, "Principles of the ballistic magnetometer for the measurements of remanence," Developments in Solid Earth Geophysics, Vol. 3, pp. 105-114 (2013)
  16. B. D. Cullity, "Introduction to Magnetic Materials," Addison-Wesley, Reading, MA, p. 317 (1972)
  17. G. A. Webster and R. A. Ainsworth, "High Temperature Components Life Assessment," Chapman & Hall, London, p. 26 (1994)
  18. K. Davut and C. H. Gur, "Monitoring the microstructural changes during tempering of quenched SAE 5140 steel by magnetic Barkhausen noise," Journal of Nondestructive Evaluation, Vol. 26, pp. 107-113 (2007) https://doi.org/10.1007/s10921-007-0025-x
  19. C, S. Kim, C. J. Lissenden, I. K. Park and K. S. Ryu, "Dynamic coercivity of advanced ferrite steel during long-term isothermal aging," Materials Transaction, Vol. 50, No. 11, pp. 2691-2694 (2009) https://doi.org/10.2320/matertrans.M2009170