Analysis of fretting conditions in pinned connections

• Published in: Wear 1995-03, Vol.181, p.524-530
• Main Authors: Iyer, K., Hahn, G.T., Bastias, P.C., Rubin, C.A.
• Format: Article
• Language: English
• Subjects: Contact pressure; Fretting; Pinned connections; Slip amplitude
• ISSN: 0043-1648; 1873-2577
• DOI: 10.1016/0043-1648(95)90167-1

A 2-dimensional, finite element model of a pinned connection, involving AA7075-T6 aluminum alloy sheet and aluminum and steel pins, is used to evaluate the local mechanical parameters that control fretting wear damage. These include the contact pressure, the slip amplitude, the tensile stress parallel to the hole interface and a fretting wear ( F 1) and fretting fatigue ( F 2) parameter. The connection is subjected to cyclic loading with a peak nominal stress of σ = 125 MPa and R = 0.1. The dimensions and constraints of the model approximate those of multi-riveted panels. Values of interference in the range 0–2% interference, and 2 values of the coefficient of friction, μ=0.2 and μ = 0.5, are examined. The variations of the mechanical parameters with angular position about the hole are defined. Peak contact pressures in the range p = 500–600 MPa are obtained at the pin-bore interface. The slip amplitudes in the range 2 μm < δ < 20 μm, and circumferential tensile stresses as high as σ ≈100 MPa, are produced in regions where the contact pressure is generally above p = 400 MPa. The peak values of the fretting wear parameter, 0.3 kPa m < F 1 < 3 kPa m, coupled with small slip amplitudes and specific wear rates cannot account for significant material loss in the stiff model connection examined here. However, the relatively large fretting fatigue parameter values, 6 × 10 10 Pa m < F 2 < 70 × 10 10 Pa m, could promote early fretting fatigue failure in the absence of interference.