Experimental evaluation of fretting fatigue test apparatus

An unique fretting fatigue test rig has been designed and fabricated to characterize the fretting fatigue damage process with a facility to view the crack which is being initiated in and around the contact zone during the test. The test rig incorporates load cells for normal and friction force measurements. The complete calibration details for the custom built load cells for normal and friction force measurements are furnished. The fretting fatigue experiments have been conducted with 7075-T6 aluminium alloys to demonstrate the capability of the fretting fatigue test rig. Clear crack initiation microscopic results provided. The crack initiation cycles reduces with an increase in normal stress keeping axial stress amplitude at a constant value. Also the crack initiation cycles reduces with an increase in axial stress amplitude keeping normal stress at a constant value. The crack propagation results are also presented.