Improved ceramic heat exchanger materials. Final report

Technical Report · Mon Dec 01 00:00:00 EST 1980

OSTI ID:6615820

Rauch, Sr, H W; McCreight, L R

Numerous compositions were developed and evaluated for potential application as heat exchanger structures in automotive gas turbine engines. Test specimens were evaluated for thermal expansion and dimensional stability before and after exposure to sea salt and sulfuric acid, followed by thermal cycling up to 1200/sup 0/C. Materials which survived the screening tests were considered for fabrication into honeycomb form. The material finally selected, GE-7808, consists of the oxides, ZrO/sub 2/-MgO-Al/sub 2/O/sub 3/-SiO/sub 2/, and is described generically as ZrMAS. The original version on which the primary work was done was based on a commercially available cordierite (MAS) frit. Late in the program, however a clay/talc mixture was demonstrated to be a satisfactory very low cost source of the cordierite (MAS) phase. Several full size honeycomb regenerator cores, about 10.2 cm thick and 55 cm dia were fabricated from both the frit and mineral versions of GE-7808. The honeycomb cells in these cores had rectangular dimensions of about 0.5 mm x 2.5 mm and a wall thickness of approximately 0.2 mm (0.008''). Test specimens cut from the cores were evaluated. The multi-phase materials developed in this program demonstrated that their refractoriness and rheological behavior enabled them to retain shape and orientation of the gas passages parallel to the axis much better than some single phase (glass ceramic) materials. The test data show that GE-7808 is significantly more stable at 1100/sup 0/C in the presence of sodium than the Corning 9460 aluminosilicate reference materials.Overall assessment of GE-7808 properties, ease of material preparation, noncritical materials utilized and ready adaptability to honeycomb fabrication qualify this new material as a candidate for heat exchanger applications in automotive gas turbine engines.

• Research Organization: General Electric Co., Philadelphia, PA (USA). Advanced Energy Programs Dept.
• DOE Contract Number: EC-77-A-31-1011
• OSTI ID: 6615820
• Report Number(s): DOE/NASA/9698-2; NASA-CR-159678
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
AUTOMOBILES
GAS TURBINE ENGINES
HEAT EXCHANGERS
FABRICATION
MATERIALS
CERAMICS
CORROSION
MATERIALS TESTING
RESEARCH PROGRAMS
SODIUM
THERMAL EXPANSION
ALKALI METALS
CHEMICAL REACTIONS
ELEMENTS
ENGINES
EXPANSION
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
METALS
TESTING
VEHICLES
330103* - Internal Combustion Engines- Turbine