Thickness Effect of 2195 Al-Li Alloy Friction Stir Weld Fracture Toughness.

For damage tolerance design in engineering components, the fracture toughness value, , of the material is essential. However, obtaining specimens of sufficient thickness from stir friction welded plates is challenging, and often, the experimental test values do not meet the necessary criteria, preventing the experimental fracture toughness, , from being recognized as plane strain fracture toughness . The fracture toughness of 2195 Al-Li alloy welding seams with different thicknesses was measured on the forward and backward sides.