Dynamic cracking resistance of structural materials predicted from impact fracture of an aircraft alloy
- 47 Downloads
A new approach to studying the dynamic strength properties of structural materials is demonstrated with fracture of 2024-T3 aircraft aluminum alloy. The central idea of this approach is the incubation time to failure. In , experimental data for dynamic fracture of this alloy were analyzed in terms of the classical fracture criterion, which is based on the principle of maximum critical stress intensity factor . In , the dependence of the stress intensity factor limiting value (the dynamic fracture toughness KId, which was assumed to be a functional characteristic of the material) on the loading rate was also measured. The same experimental data were analyzed in terms of an alternative structure-time approach . In this approach, the dynamic fracture toughness KId is considered as an estimable characteristic of the problem, so that determination of limiting loads does not require a priori knowledge of the loading-rate dependence of the dynamic fracture toughness. The incubation time to failure of the aircraft aluminum alloy is calculated. The difference in the loading-rate dependences of the dynamic fracture toughness, which is observed for various structural materials, is explained. The dynamic fracture toughness of the alloy under pulsed threshold loads is calculated.
KeywordsFracture Toughness Incubation Time Stress Intensity Factor Critical Stress Fracture Criterion
Unable to display preview. Download preview PDF.
- 2.G. Irwin, J. Appl. Mech. 24, 361 (1957).Google Scholar
- 3.Yu. V. Petrov, Preprint (Inst. for Problems of Mechanical Engineering, Russ. Acad. Sci., St. Petersburg, 1996), pp. 9–12.Google Scholar
- 4.D. A. Shockey, D. C. Erlich, J. F. Kalthoff, et al., Eng. Fract. Mech. 23, 311 (1986).Google Scholar
- 5.A. N. Berezkin, S. I. Krivosheev, Yu. V. Petrov, et al., Dokl. Akad. Nauk 375, 328 (2000) [Dokl. Phys. 45, 617 (2000)].Google Scholar