Fatigue crack propagation in explosive bonded LY12/20g double-layer metal laminate: II. Angle-crack

The fatigue angle crack growth behavior of explosive bonded double-layer metal composite plates (LY12/20g) was investigated. The results indicate that the properties of the interface and the components have significant influence on the fatigue crack growth. To double layer plates with different components, during the fatigue crack propagation, the crack lengths on two sides surface of the same specimen are not the same. Their difference Δa increases with the fatigue crack growth and has a maximum value Δa_c. The fatigue crack growth rates of two sides of the same specimen are not the same if Δa < Δa_c, and after Δa ≥ Δa_c the fatigue crack growth rates are the same. The suitable characterization of the fatigue crack propagation in double layer laminates should use both the Δa_c and the curve of ΔK-da/dN of one side after Δa = Δa_c.