Influence of Material State at a Crack Tip on the Process of Fatigue Striations Formation for Al-Based Alloys
Fatigue fracture features such as pseudo- and fatigue striations were investigated for the Al-alloys AL-Si-Mg and Acoustic Emission (AE) was used to analyze plastic deformation processes ahead of a crack tip. Dramatic change of fatigue striations spacing was demonstrated in accordance with AE-signals evolution. Specimens with fatigue crack have not macroscopic significance in plastic deformation process under tension up to the fast fracture when striation spacing is over 2.1x10-7 m. Mechanisms of material deformation and fracture around of a crack tipduring fatigue striations formation process are discussed on the bases of the synergistic approach.
A.A. Shaniavski "Influence of Material State at a Crack Tip on the Process of Fatigue Striations Formation for Al-Based Alloys", Materials Science Forum, Vol. 482, pp. 235-238, 2005