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Elevated temperature intergranular cracking of heat-resistant alloy under tensile stress

Published online by Cambridge University Press:  05 April 2011

Nam-Hoe Heo  and
Jung-Chel Chang
Nam-Hoe Heo*
Affiliation:
KEPCO Research Institute, Yusung-Gu, Daejeon 305-380, Republic of Korea
Jung-Chel Chang
Affiliation:
KEPCO Research Institute, Yusung-Gu, Daejeon 305-380, Republic of Korea
*
a)Address all correspondence to this author. e-mail: nhheo@kepri.re.kr
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Abstract

In a 2.25Cr1.5W heat-resistant alloy, it is shown that the time to intergranular failure under tensile stress t can be expressed by , where t0 is the constant of proportionality, n is the stress exponent, and Q is the activation enthalpy. It is shown that the dimples observed at elevated-temperature intergranular fracture surfaces are not the micro-ductile fracture areas but the interfaces between the grain boundary carbides and the neighboring grains. It is also shown that the segregation concentration of solute atoms is much higher at the grain boundary carbide interfaces than at the carbide-free grain boundaries. Under tensile stress, the elevated-temperature intergranular cracking occurs through the decohesion of grain boundary carbide interfaces, which is followed by the eventual carbide-free grain boundary cracking.

Keywords

Auger Electron Spectroscopy(AES)FractureEmbrittlement
Type
Articles
Information
Journal of Materials Research , Volume 26 , Issue 8 , 28 April 2011 , pp. 1006 - 1011
Copyright
Copyright © Materials Research Society 2011

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References

REFERENCES

1.Shinoda, T. and Nakamura, T.: The effects of applied stress on the intergranular phosphorus segregation in a chromium steel. Acta Metall. 29, 1631 (1981).CrossRefGoogle Scholar
2.Misra, R.D.K.: Issues concerning the effects of applied tensile stress on intergranular segregation in a low alloy steel. Acta Mater. 44, 885 (1996).CrossRefGoogle Scholar
3.Lee, J.R. and Chiang, Y.M.: Pressure-thermodynamic study of Bi segregation at ZnO grain boundaries. Mater. Sci. Forum. 207–209, 129 (1996).CrossRefGoogle Scholar
4.Hippsley, C.A., Knott, J.E., and Edwards, B.C.: A study of stress relief cracking in 2.25Cr-1Mo steel-1. The effect of P segregation. Acta Metall. 28, 869 (1980).CrossRefGoogle Scholar
5.Hull, D. and Rimmer, D.E.: The growth of grain boundary voids under stress. Philos. Mag. A 4, 673 (1959).CrossRefGoogle Scholar
6.Speight, M.V. and Harris, J.E.: The kinetics of stress-induced growth of grain-boundary voids. Meat Sci. 1, 83 (1967).Google Scholar
7.Raj, R. and Ashby, M.F.: Intergranular fracture at elevated temperature. Acta Metall. 23, 653 (1975).CrossRefGoogle Scholar
8.Chuang, T.J., Kagawa, K.I., Rice, J.R., and Sills, L.B.: Overview no. 2: Non-equilibrium models for diffusive cavitation of grain interfaces. Acta Metall. 27, 265 (1979).CrossRefGoogle Scholar
9.Bailey, N.: Weldability of Ferritic Steels (Woodhead Publishing Ltd., Cambridge, England, 1994).CrossRefGoogle Scholar
10.Balaguer, J.P., Wang, Z., and Nippes, E.F.: Stress-relief cracking of a copper- containing HSLA steel. Weld. J. 68, 121 (1989).Google Scholar
11.Nawrocki, J.G., Dupont, J.N., Robino, C.V., Puskar, J.D., and Marder, A.R.: The mechanism of stress-relief cracking in a ferritic alloy steel. Weld. J. 82, 25 (2003).Google Scholar
12.Nawrocki, J.G., Dupont, J.N., Robino, C.V., Puskar, J.D., and Marder, A.R.: The stress-relief cracking susceptibility of a new ferritic steel: Part 1. Single-pass heat-affected zone simulations. Weld. J. 79, 355 (2000).Google Scholar
13.Shin, J. and McMahon, C.J. Jr: Mechanisms of stress relief cracking in a ferritic steel. Acta Metall. 32, 1535 (1984).CrossRefGoogle Scholar
14.Bika, D., Pfaendtner, J., Menyhard, M., and McMahon, C.J. Jr.: Sulfur-induced dynamic embrittlement in a low-alloy steel. Acta Metall. 43, 1895 (1995).CrossRefGoogle Scholar
15.Geng, W.T., Freeman, A.J., and Olson, G.B.: Influence of alloying additions on the impurity induced grain boundary embrittlement. Solid State Commun. 119, 585 (2001).CrossRefGoogle Scholar
16.Lee, D.Y., Barrera, E.V., Stark, J.P., and Marcus, H.L.: The influence of alloying elements on impurity induced grain boundary embrittlement. Metall. Trans. 15A, 1415 (1984).CrossRefGoogle Scholar
17.Weng, Y.Q. and McMahon, C.J. Jr.: Interaction of phosphorus, carbon, manganese, and chroumium in intergranular embrittlement of iron. Mater. Sci. Technol. 3, 207 (1987).Google Scholar
18.Van Der Brug, M.W.D., Van Der Giessen, E., and Brouwer, R.C.. Investigation of hydrogen attack in 2.25Cr-1Mo steels with a high-triaxiality void growth model. Acta Metall. 44, 505 (1996).Google Scholar
19.Raj, R.: Nucleation of cavities at second phase particles in grain boundaries. Acta Metall. 26, 995 (1978).CrossRefGoogle Scholar
20.Hondros, E.D. and Seah, M.P.: Segregation to interfaces. Inter. Metals Rev. 222, 262 (1977).Google Scholar
21.Lea, C. and Seah, M.P.: Kinetics of surface segregation. Philos. Mag. 35, 213 (1977).CrossRefGoogle Scholar
22.Grant, N.J.: Utilization of Heat Resistant Alloys (ASM, OH, 1954).Google Scholar