Finite element analysis of metal casting around low expansion ceramic metals

Conference · Tue Aug 01 04:00:00 EDT 1995

OSTI ID:86600

Limaye, S Y ^[1]; Coors, D ^[2]; Lehto, M A ^[3]

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1. LoTEC, Inc., West Valley City, UT (United States)
2. Golden Technologies, Golden, CO (United States)
3. RAE Corp., Salt Lake City, UT (United States)

Low thermal expansion ceramics such as NZP ceramic and Aluminum titanate are considered prime candidates for exhaust port liners of diesel engines due to their excellent thermal shock resistance and low thermal conductivity. The exhaust port liners under development at LoTEC, Inc., and Golden Technologies are a composite, cast metal-ceramic part. During the metal-ceramic casting and production process, a thermal expansion mismatch between the metal and ceramic creates large stresses that ultimately have lead to the failure of the metal-ceramic exhaust port liners. The objective of this research program was to develop ceramic-based {open_quotes}cast-in-place{close_quotes} diesel engine port liners. The first phase of the research program involved analyzing materials requirements through finite element modeling, characterizing thermo-mechanical and microstructural properties of the ceramics, conducting metal-ceramic casting trials to verify the finite element modeling work, and developing a cost-effective ceramic fabrication process. A metal-ceramic casting test plan was implemented to analyze temperature distributions and associated thermal stresses in the ceramic-lined metal parts. Through a process of experimental measurements and finite element modeling, a modification was made in the metal casting process. This modification, derived from predictions stemming from the finite element modeling of the casting process, involves placing a uniquely made, compliant ceramic layer. This modification results in successful casting of the exhaust port liners because it allows the system to bond together without introducing large stresses on the outer ceramic wall. Details of the finite element analysis and the progress to date from instrumented metal-ceramic casting trials are presented in this paper.

• OSTI ID: 86600
• Report Number(s): CONF-940416--
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
36 MATERIALS SCIENCE
CASTINGS
DIESEL ENGINES
FABRICATION
FINITE ELEMENT METHOD
LINERS
MICROSTRUCTURE
THERMAL EXPANSION