Hostname: page-component-586b7cd67f-t7fkt Total loading time: 0 Render date: 2024-11-29T09:35:45.460Z Has data issue: false hasContentIssue false

Role of Cyclic Deformation in Controlling Grain Boundary Fracture in Fatigue

Published online by Cambridge University Press:  26 February 2011

Fei-Lin Liang
Affiliation:
Dept. of Metallurgy and Materials Sci., Polytechnic University, 333 Jay St., Brooklyn, NY 11201
Campbell Laird
Affiliation:
Dept. of Materials Sci. & Eng., University of Pennsylvania, 3231 Walnut St., Philadelphia, PA 19104-6272
Get access

Abstract

Recent studies of long life fatigue have shown fractures to initiate primarily at grain boundaries, even in copper. This is considered surprising in light of early work where crack nucleation in persistent slip bands (PSB´s) seemed to be the rule. To investigate the causes of this behavior, studies have been carried out on polycrystalline copper with emphasis on the following factors: grain size, environment, method of starting the test, frequency and mode of test control.

The results show that the cyclic plasticity is the controlling factor in grain boundary initiation and propagation of fatigue cracks. These conducted in load or strain control, even at low amplitudes, homogenized the deformation and cause grain boundary failure. Tests started by ramp loading emphasize localized strain, PSB formation and thus, transgranular cracking. An aggressive environment stimulates intergranular failure but is not controlling. Likewise a small grain size tends to promote strain localization.

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. Laird, C. and Duquette, D.J., in Corrosion Fatigue, edited by Devereaux, O.J., McEvily, A.J., and Staehle, R.W. (NACE-2, Houston, TX, 1972) pp. 88117.Google Scholar
2. Figueroa, J.C., Ph.D. thesis, U. ofn Penn., 1979.Google Scholar
3. Figueroa, J.C. and Laird, C., Mat. Sci. Eng., 60, 45 (1983).CrossRefGoogle Scholar
4. Mughrabi, H., Wang, R., Differt, K., and Essmann, U., in Fatigue Mechanisms: Advances in Ouantitative Measurement of Physical Damage, edited by Lankford, J., et al. (ASTM STP 811, 1983) pp. 545.CrossRefGoogle Scholar
5. Mughrabi, H. and Wang, R., in Defects, Fracture and Fatigue, edited by Sih, G.C. and Zorski, H. (Martinus Nijhoff Publishers, Hague, 1983) p. 139.CrossRefGoogle Scholar
6. Yan, B., Hunsche, A., Neumann, P., and Laird, C., Mat. Sci. Eng., 79, 9 (1986).Google Scholar
7. Kim, W. H. and Laird, C., Acta Metall., 26, 789 (1978).CrossRefGoogle Scholar
8. Yan, B. and Laird, C., Mat. Sci. Eng., 80, 59 (1986).Google Scholar
9. Wood, W. A. and Head, A. K., J. Inst. Metals, 79, 89 (1951).Google Scholar
10. Kemsley, D. S., J. Inst. Metals, 85, 153 (1956-1957).Google Scholar
11. Mason, W. P. and Wood, W. A., J. Appl. Phys., 39, 5581 (1968).CrossRefGoogle Scholar