Study on Fatigue Crack Growth Model of 7075-T7410 Aluminum Alloy Straight Attachment Lug

Abstract:

The finite element model of a 7075-T7410 straight attachment lug is built by using the finite element software ANSYS, a cosine distribution pin-bearing pressure is applied on the surface of the pin-hole as a boundary condition. The stress intensity factor (SIF) expression for the straight attachment lug with a single through-the-thickness crack and subjected to an axial pin-load is determined by studying on the effect of the geometric parameters (the dimensionless crack length a/R₁，the ratio of outer radius to inside radius R₂/R₁ and the inside radius R₁) on SIF value. The fatigue crack growth velocity (da-dN) and the stress intensity factor’s amplitude (ΔK) is calculated by the SIFs equations to get the values of the Paris constants, offering an analytical method for establishment of the fatigue crack growth model of the typical straight lugs. The paper can be helpful in assessing and designing damage tolerant attachment lugs.

• Periodical: Applied Mechanics and Materials (Volumes 66-68)
• Pages: 82-89
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.66-68.82
• Online since: July 2011
• Authors: Li Ming Wu, Yu Ting He, Xin Bo Wang, Hai Wei Zhang, Jin Qiang Du, Hua Ding
• Keywords: Attachment Lug, Fatigue Crack Growth (FCG), Finite Element Model (FEM), Paris Law, Stress Intensity Factor (SIF)

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