Failure Analysis of Over-Temperature of Aero-Engine Bearing

The analysis of aero-engine bearings is crucial for the advancement of aero-bearing technology and the improvement of the reliability of aero-engines. During a test of an aero-engine spindle bearing, an abnormal noise was detected. Upon investigation of the damaged bearing, a failure analysis was conducted through various methods including macroscopic and microscopic observation, metallographic analysis, and hardness testing. The results indicated that the shift of the contact position between the steel balls and the inner ring raceway was due to a heavy axial load. Abnormal wear between the inner race and balls resulted in overheating, which then caused the volumetric expansion of the inner race and contacted the cage. This led to abnormal adhesive wear between the inner ring and the cage, ultimately causing the bearing failure.