This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Isostatic Strength of Porous Cordierite Ceramic Monoliths
Annotation ability available
Sector:
Language:
English
Abstract
The isostatic strength of porous cordierite ceramic monoliths plays an important role during canning and subsequent operation of automotive catalysts. Its value depends on wall porosity, cell geometry, skin thickness and morphology, monolith size and contour, and substrate/washcoat interaction. If the stresses induced by canning loads and closure speeds exceed the isostatic strength, the monolith may exhibit either crushing or shear type failure.
This paper presents the room temperature isostatic strength data for coated and uncoated ceramic monoliths of different contour, size, and cell geometry. The applied isostatic load on the monolith is translated into stresses in the porous cell wall using both an analytical model and finite element analysis. It is found that the failure criteria are governed by the fundamental tensile and compressive strengths of the cell wall. The addition of alumina washcoat increases the isostatic strength as long as the substrate/washcoat interaction is carefully controlled during the coating process. The higher isostatic strength of coated monoliths facilitates the canning process and permits higher holding pressure, thereby enhancing their physical durability over the specified lifetime of the vehicle.
Recommended Content
Authors
Citation
Gulati, S. and Chen, D., "Isostatic Strength of Porous Cordierite Ceramic Monoliths," SAE Technical Paper 910375, 1991, https://doi.org/10.4271/910375.Also In
References
- Gulati S.T. Sweet R.D. “Strength and Deformation Behavior of Cordierite Substrates from 70° to 2550°F,” SAE Paper No. 900268 February 1990
- Gulati S.T. Pujari V.K. “Mechanical Integrity of Ceramic Monolithic Converters,” SAE Paper 811324 November 1981
- Stroom P.D. Merry R.P. Gulati S.T. “Systems Approach to Packaging Design for Automotive Catalytic Converters,” SAE Paper No. 900500 February 1990
- Gulati S.T. “New Developments in Catalytic Converter Durability,” CAPoC-2 Conference Brussels 1990
- Gulati S.T. “Long-Term Durability of Ceramic Honeycombs for Automotive Emissions Control,” SAE Paper No. 850130 February 1985
- Kawakami T. Furuya T. Sasaki Y. Yoshine T. Furuse Y. Hoshino M. “Feasibility Study on Honeycomb Ceramics for Catalytic Combustor,” ASME Paper No. 89GT-41 Toronto June 1989
- Chen D.K.S. “Mechanical Behavior and Strength of Ceramic Cellular Substrate - A Microscopic View,” ASME Winter Annual Meeting Dallas, TX November 1990
- Chen D.K.S. Verma A. “Integrity of Automotive Catalytic Converter During Assembly Process,” ASME Winter Annual Meeting Dallas, TX November 1990
- Gulati S.T. “Strength of Cordierite Honeycomb Ceramics,” 1987 Annual Meeting of Am. Ceram. Soc. Pittsburgh, PA
- Gulati S.T. “Cell Design for Ceramic Monoliths for Catalytic Converter Application,” SAE Paper No. 881685 October 1988
- Gulati S.T. Summers J.C. Linden D.G. White J.J. “Improvements in Converter Durability and Activity via Catalyst Formulation,” SAE Paper 890796 February 1989
- Weibull W. “A Statistical Distribution Function of Wide Applicability,” J. App. Mech. 1951
- Timoshenko S.P. Goodier J.N. Theory of Elasticity 3rd. McGraw-Hill New York 1970