Premium
FATIGUE CRACK GROWTH RATES IN Al–Li ALLOY, 2090. INFLUENCE OF ORIENTATION, SHEET THICKNESS AND SPECIMEN GEOMETRY
Author(s) -
Mc FJ,
Tabrett CP,
Smith DJ
Publication year - 1998
Publication title -
fatigue and fracture of engineering materials and structures
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.887
H-Index - 84
eISSN - 1460-2695
pISSN - 8756-758X
DOI - 10.1046/j.1460-2695.1998.00428.x
Subject(s) - materials science , paris' law , alloy , composite material , aluminium , crack closure , orientation (vector space) , geometry , metallurgy , fracture mechanics , mathematics
.The fatigue crack growth (FCG) behaviour of the aluminium–lithium (Al–Li) alloy 2090‐T84 has been investigated from a series of constant amplitude FCG tests. The influence of in‐plane orientation (L–T, T–L, L–T + 45°) and sheet thickness (1.6 and 6 mm) on the FCG rates for the rolled product has been examined. In general, the T–L orientation possesses superior FCG resistance for both thicknesses and the 6 mm thick sheet material showed marginally improved FCG resistance when compared to the 1.6 mm thick material, for all orientations. Closure‐corrected FCG data suggests that much of the difference between the L–T and T–L orientation for the 6 mm thick sheet arises from differences in crack closure levels. When comparing the crack closure levels for C(T) and M(T) specimens, a significant difference is shown as ΔK increases. Fatigue crack growth rates for ΔK less than 15 MPa m were significantly higher in the M(T) specimens compared to the C(T) specimens. Compared with other factors examined the influence of specimen geometry appears to be a dominant factor.