Rolling Contact Fatigue of Hot-Pressed Silicon Nitride Versus Surface Preparation Techniques
Hot-pressed silicon nitride is receiving interest as a potential antifriction bearing material1. As a result of advanced material preparation and processing techniques, bend strengths in excess of 100,000 psi are routinely achieved. In addition to its high strength, dimensional stability and corrosion resistance, silicon nitride has a density of 3.2 g/cm3, sixty percent lower than that of steel. This light weight is especially important for high speed bearings, where the maximum stresses occur in the outer race, primarily as a result of the centrifugal force loading from the rolling elements. Inasmuch as strength tends to be sensitive to surface integrity, finishing procedures are an important aspect for bearing applications. This paper will report experiments on their effect.
KeywordsFatigue Porosity Dust Carbide Depression
Unable to display preview. Download preview PDF.
- 1.Wheildon, W. M., Baumgartner, H. R., Sundberg, D. V. and Torti, M. L., “Ceramic Materials in Rolling Contact Bearings”, Final Report on Contract N00019-72-C-0299, 1973.Google Scholar
- 2.Alliegro, R. A., Richerson, D. W., Torti, M. L., Washburn, M. E., and Weaver, G. Q., “Silicon Nitride and Silicon Carbide for High Temperature Engineering Applications”, to be published in Proceedings of the British Ceramic Society Convention, July 1972.Google Scholar
- 3.Bamberger, E. N. and Baughman, R. A., “Development of Fatigue Data for Bearing Materials,” General Electric Report No. R57AGT712, FPJLD, November, 1957.Google Scholar
- 6.Schneider, Jr., S. J. and Rice, R. W. eds., The Science of Ceramic Machining and Surface Finishing, U.S. Nat. Bur. Stds. Spec. Pub. 348, (1972).Google Scholar
- 7.Sedlacek, R. and Jorgensen, P. J., “Processing of Ceramics — Surface Finishing Studies”, Final Technical Report of Contract No. N00019-70-C-0179, September 1971.Google Scholar
- 8.Pears, C. D., Starret, H. S., Bickelhaupt, R. E. and Braswell, D. W., “A Quantitative Evaluation of Test Methods for Brittle Materials”, Technical Report AFML-TR-69-244, Part I, March 1970.Google Scholar