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Spall Propagation-Resistant Hybrid Bearings for High-Performance Turbine Engines

Award Information

Department of Defense
Air Force
Award ID:
Program Year/Program:
2008 / SBIR
Agency Tracking Number:
Solicitation Year:
Solicitation Topic Code:
Solicitation Number:
Small Business Information
UES, Inc.
4401 Dayton-Xenia Road Dayton, OH -
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Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Phase 1
Fiscal Year: 2008
Title: Spall Propagation-Resistant Hybrid Bearings for High-Performance Turbine Engines
Agency / Branch: DOD / USAF
Contract: FA8650-08-M-2835
Award Amount: $99,855.00


The objective of this SBIR project is to develop spall propagation resistant turbine engine mainshaft bearings for improved reliability, safety, and performance margin of aircraft propulsion systems. New case carburized Pyrowear 675 steel has been developed for bearing races that has been shown to resist surface fatigue initiation and therefore improve the fatigue life compared to the M50 steel. However, once the initiation occurs, fatigue cracks can propagate rapidly resulting in increased spall rate in Pyrowear 675 races. This aspect of the fatigue properties of Pyrowear 675 has not been studied in great detail. In this Phase I SBIR project, UES proposes to identify the key properties of Pyrowear 675 such as microstructure, and near-surface fracture toughness that control the spall propagation rate. For this purpose, Rolling Contact Fatigue tests will be conducted under selected stress cycles, and the neighborhood of spalled area will be investigated. Spalled areas of failed bearings will also be investigated, if available. Also, computer modeling and simulation will be used to understand the role of dynamic operating conditions such as load and speed on the spall propagation.

Principal Investigator:

Rabi S. Bhattacharya
Div Dir/Prin Research Scientis

Business Contact:

Francis F. Williams, Jr.
Contracts Manager
Small Business Information at Submission:

4401 Dayton-Xenia Road Dayton, OH 45432

EIN/Tax ID: 310797776
Number of Employees:
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No