Abstract
Thermo-Calc and Dictra commercial calculation software programs have been used to simulate the formation of fine microstructure of 9%Ni cryogenic steel processed by quench–lamellarize–temper (QLT) heat treatment. The calculations show many compositional fluctuations in each single-martensite lath after QLT treatment; the peak concentrations of carbon and nickel reach about 0.40 % and 18 %, respectively. The width of the C or Ni element-enriched zone increases when the critical lamellarizing temperature decreases or the temper temperature increases. Extending the temper time has a similar effect on the element profiles. The simulation results are in accordance with the observed fine microstructures.
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Acknowledgments
The authors are grateful to Dr. Pingfang Shi from Thermo-Calc software AB, Sweden and staff from the CISRI-TCS union open lab for providing technical and software support. This work was supported by the National High Technology Research and Development Program of China (2007AA03Z506) and Key Projects in the National Science & Technology Pillar Program (2007BAE51B06).
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SPECIAL ISSUE: Materials Genome
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Pan, T., Zhu, J., Yang, C. et al. Kinetics simulation and experimental observation of fine microstructure of 9%Ni cryogenic steel processed by QLT heat treatment. Chin. Sci. Bull. 59, 1765–1772 (2014). https://doi.org/10.1007/s11434-014-0139-3
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DOI: https://doi.org/10.1007/s11434-014-0139-3