Accession Number:
ADA317259
Title:
Engine Hybrid Ceramic Bearings.
Descriptive Note:
Final rept. 23 May 92-23 Nov 94,
Corporate Author:
GE AIRCRAFT ENGINES CINCINNATI OH
Personal Author(s):
Report Date:
1994-11-01
Pagination or Media Count:
118.0
Abstract:
The objective of this program was the development of additional performance data and condition-monitoring techniques for silicon nitride Si3N4 bearings. Induced-defect testing was performed to assess the ability of silicon nitride balls to withstand the high shock loads experienced during the growth of a race spall. The defect was placed in the outer ring of a hybrid bearing. Conclusions were made as to the survivability of ceramic balls under such severe conditions. High-speed thermal performance was compared between an all-steel bearing, a hybrid with the same internal geometry, and a hybrid with tightened internal geometry to lower the hertzian contact stress. Conclusions were made as to whether the hybrid bearings offer any improvement in thermal performance over an all-steel bearing. A condition-monitoring methodology was developed for early detection of an impending bearing failure. A technique was developed to find both metallic and ceramic debris from bearings. A monitoring device was developed, constructed, and demonstrated.
Descriptors:
- *ROLLER BEARINGS
- *SILICON NITRIDES
- *BALL BEARINGS
- TEST AND EVALUATION
- RISK
- FATIGUE LIFE
- MONITORING
- AIRCRAFT ENGINES
- HIGH TEMPERATURE
- HIGH VELOCITY
- FRACTURE(MECHANICS)
- CERAMIC MATERIALS
- GAS TURBINES
- DEFECTS(MATERIALS)
- IMPACT SHOCK
- INFRARED DETECTORS
- FAILURE(MECHANICS)
- SHOCK TESTS
- THERMAL STRESSES
- THERMAL SHOCK
- CRANKSHAFTS
Subject Categories:
- Ceramics, Refractories and Glass
- Jet and Gas Turbine Engines