Hostname: page-component-77c89778f8-n9wrp Total loading time: 0 Render date: 2024-07-18T16:10:23.003Z Has data issue: false hasContentIssue false

Carbon Segregation Induced Grain Boundary Embrittlement

Published online by Cambridge University Press:  26 February 2011

W.W. Gerberich
Affiliation:
Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455
X. Chen
Affiliation:
Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455
R. Caretta
Affiliation:
Surface Analysis Center, University of Minnesota, Minneapolis, MN 55455
Get access

Abstract

To investigate the mechanisms of grain boundary embrittlement, sustained load tests were conducted on a medium carbon, high strength martensitic steel at slightly elevated temperatures. Slow crack growth was observed from 185°C to 500°C.

Fracture surfaces of the specimens tested were examined by scanning electron microscopy after sustained load tests. It was found that severe grain boundary embrittlement occurred in this material with the predominant fractographic feature being intergranular fracture.

Auger electron and x-ray photoelectron spectroscopy of the intergranular facets were utilized to analyze the embrittling species. Prior suggestions for this “strain-aging embrittlement” phenomena have centered around carbide precipitation. The present results suggest that it is carbon, driven by thermal energy and the stress field, that segregates on the grain boundaries and weakens them.

Type
Research Article
Copyright
Copyright © Materials Research Society 1988

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Troiano, A.R., Trans. ASM. 52 54 (1960).Google Scholar
2. Steigerward, E.A. and Hanna, G.L., Trans. Quart. ASM 56(3), 656 (1963).Google Scholar
3. Gerberich, W.W., Hartbower, C.E. and Crimmins, P.P., Welding Journal Research Supplement 433s (Oct. 1968).Google Scholar
4. Gerberich, W.W., Hartbower, C.E. and Chen, X., “Internal Carbon Embrittlement,” in “Proceedings of the third International Conf. of Environmental Degradation of Engineering Materials,” eds. Louthan, M.R. Jr., McNitt, R.P. and Sisson, R.D. Jr., Penn. State Univ. P105 (April 1987).Google Scholar
5. ASTM Standard E399-81, Annual Book of ASTM Standards, Part 10, 1981.Google Scholar
6. Gerberich, W.W. and Chen, X. “A Kinetic Model for Internal Carbon Embrittle-meat” unpublished results.Google Scholar