About this Abstract |
Meeting |
MS&T24: Materials Science & Technology
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Symposium
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Engineering Ceramics: Microstructure-Property-Performance Relations and Applications
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Presentation Title |
Influence of Various Operating Conditions on Co-Annular Silicon Nitride-Based Glow Plug Degradation |
Author(s) |
Prapassorn Numkiatsakul, Cory Philippe, Eri Amezcua Cuellar, David Rothamer, Tonghun Lee, Kenneth Kim, Chol-Bum Kweon, Waltraud Kriven |
On-Site Speaker (Planned) |
Prapassorn Numkiatsakul |
Abstract Scope |
Silicon nitride-based composites are widely used in ceramic heaters for combustion engines due to their high strength and wear resistance. Recent developments in engine designs, focusing on using alternative jet fuels with lower auto-ignition tendencies, have increased the demand for ignition-assisted devices. However, extended operation of glow plugs at high temperatures, beyond their intended use, accelerates degradation processes, reducing durability. To design improved materials for this application, investigating the failure modes of state-of-the-art glow plugs is crucial. This paper presents experimental results of co-annular glow plugs from three operating environments: benchtop tests, constant flow chambers, and combustion engines. SEM microscopy was used to study the microstructure. Degradation observed in co-annular designs included surface oxidation, phase segregation of Si3N4 and MoSi2, and internal cracks caused by thermal stress from CTE mismatch. The primary failure mode of this glow plug design is surface oxidation due to heat generation in the outermost layer. |