Damage Tolerance Properties of 2198-T8 Integral Fuselage Panel between Double Friction Stir Weld Joints
Al-Li alloy 2198-T8 was used in the fuselage application. Integral fuselage panels were joined by double friction stir welds. Fatigue tests were conducted in the R=0.1. Notch was made between two welds. Residual stresses were measured and analyzed in the test samples with double welds. Cracks grew from the centre of two welds and across the two welds were observed, and crack growth rates were measured and compared with parent material. It is shown that crack growth rates are lower between double welds, and it is close to parent material after cross the two welds. The virtual crack closure technique (VCCT) method was used to calculate stress intensity factor from residual stress (Kres) in aim to explain the experimental findings.
Y. E. Ma et al., "Damage Tolerance Properties of 2198-T8 Integral Fuselage Panel between Double Friction Stir Weld Joints", Applied Mechanics and Materials, Vols. 138-139, pp. 651-656, 2012