Fretting Fatigue Fracture Analysis of 2024 Aluminum Alloy under Alternating Normal Load
Aiming at the fretting fatigue failure problem widely existing in the mechanical structures,the influence of partial slip and gross slip on the fatigue fracture of 2024 aluminum alloy under alternating normal load was studied by using a biaxial fretting fatigue test system,which can apply the alternating normal load and the distal load.The fatigue fracture was analyzed by scanning electron microscope.The results show that the cracks are initiated at the contact boundary between the specimen and the fretting pad under both partial slip and gross slip mechanisms.The fracture of the partial slip specimen is caused by multiple cracks at the contact boundary and continuous fusion and expansion,and the fracture of the gross slip specimen is caused by a single crack source.The fatigue striations and strengthening phase in 2024 aluminum alloy can be seen in the crack propagation zone,and the strengthening phase in aluminum alloy can hinder the crack propagation.In addition,a large number of cleavage,quasi cleavage and torn prisms can be clearly seen.There are a lot of dimples and secondary cracks in fatigue transient fracture,showing typical ductile fracture characteristics.
2024 aluminum alloyfracture analysisfretting fatiguealternating normal load
万方数据
维普
