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Title: Evaluation of Sialon internal combustion engine components and fabrication of several ceramic components for automotive applications

Abstract

Fabrication development work was carried out on a push-rod tip having a stepped OD design and a 90{degree} shoulder in the transition area. Spray-dried Sialon premix was used in dry press tooling, and components were densified to about 98% of theoretical density using pressureless sintering conditions. Upon evaluation of the sintered components, it was found that afl components showed defects in the transition area. Modifications of the pressing parameters, incorporation of a 45{degree} angle in the shoulder area, and the use of tailored premix did not lead to the fabrication of defect-free parts. From these observations, it was concluded that the original part design could not easily be adapted to high-volume ceramic manufacturing methods. Subsequently, a modification to the desip was implemented. An SiC material with improved toughness (Hexoloy SX) was used for fabricating several test components with a closely machined, straight OD design. Pressureless-sintered and post-hot isostatically pressed (HIPed) Hexoloy SX components were supplied to The American Ceramic Engine Company (ACE) for assembly and testing. Fuel pump push-rod assemblies with Hemoloy SX tips were prepared by ACE, but no testing has been carried out to date.

Authors:
;
Publication Date:
Research Org.:
Oak Ridge National Lab., TN (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
10104381
Report Number(s):
ORNL/M-2253
ON: DE93003640
DOE Contract Number:
AC05-84OR21400
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Oct 1992
Country of Publication:
United States
Language:
English
Subject:
33 ADVANCED PROPULSION SYSTEMS; 36 MATERIALS SCIENCE; CERAMICS; HOT PRESSING; INTERNAL COMBUSTION ENGINES; MATERIALS; FABRICATION; AUTOMOBILES; SINTERING; SILICON NITRIDES; ALUMINIUM OXIDES; MANUFACTURING; SILICON CARBIDES; 330100; 360201; PREPARATION AND FABRICATION

Citation Formats

McMurtry, C.H., and Ten Eyck, M.O. Evaluation of Sialon internal combustion engine components and fabrication of several ceramic components for automotive applications. United States: N. p., 1992. Web. doi:10.2172/10104381.
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McMurtry, C.H., & Ten Eyck, M.O. Evaluation of Sialon internal combustion engine components and fabrication of several ceramic components for automotive applications. United States. doi:10.2172/10104381.
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McMurtry, C.H., and Ten Eyck, M.O. Thu . "Evaluation of Sialon internal combustion engine components and fabrication of several ceramic components for automotive applications". United States. doi:10.2172/10104381. https://www.osti.gov/servlets/purl/10104381.
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@article{osti_10104381,
title = {Evaluation of Sialon internal combustion engine components and fabrication of several ceramic components for automotive applications},
author = {McMurtry, C.H. and Ten Eyck, M.O.},
abstractNote = {Fabrication development work was carried out on a push-rod tip having a stepped OD design and a 90{degree} shoulder in the transition area. Spray-dried Sialon premix was used in dry press tooling, and components were densified to about 98% of theoretical density using pressureless sintering conditions. Upon evaluation of the sintered components, it was found that afl components showed defects in the transition area. Modifications of the pressing parameters, incorporation of a 45{degree} angle in the shoulder area, and the use of tailored premix did not lead to the fabrication of defect-free parts. From these observations, it was concluded that the original part design could not easily be adapted to high-volume ceramic manufacturing methods. Subsequently, a modification to the desip was implemented. An SiC material with improved toughness (Hexoloy SX) was used for fabricating several test components with a closely machined, straight OD design. Pressureless-sintered and post-hot isostatically pressed (HIPed) Hexoloy SX components were supplied to The American Ceramic Engine Company (ACE) for assembly and testing. Fuel pump push-rod assemblies with Hemoloy SX tips were prepared by ACE, but no testing has been carried out to date.},
doi = {10.2172/10104381},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Oct 01 00:00:00 EDT 1992},
month = {Thu Oct 01 00:00:00 EDT 1992}
}
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Technical Report:
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DOI:  10.2172/10104381
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