Abstract
Relationship between the dynamic elastic-plastic fracture toughness and the notch root radius of high strength 7075 alloys aged in various conditions were investigated. The apparent fracture toughness is strengthened with an increase of the notch root radius, ρ, and is independent of the aging condition. The notch root radius does not affect the critical value of fracture toughness, which depends on the mean free path of the inclusions over 1μm. The experimental value of critical point is slightly higher than the calculated one.
