Fig. 24 Mechanism of fatigue crack propagation by alternate slip at the crack tip. Sketches are simplified to clarify the basic concepts. (a) Crack opening and crack-tip blunting by slip on alternate slip planes with increasing tensile stress. (b) Crack closure and crack-tip resharpening More

Fig. 10 Crack tip stress-intensity control of fatigue crack propagation in 7075-T6 aluminum alloy sheet—long-transverse loading. Remote and wedge force methods of loading specimens in aqueous 3.5% sodium chloride environment and benign dry air environment. Source: Ref 46 More

Fig. 23 Mechanism of fatigue crack propagation by alternate slip at the crack tip. Sketches are simplified to clarify the basic concepts. (a) Crack opening and crack tip blunting by slip on alternate slip planes with increasing tensile stress. (b) Crack closure and crack tip resharpening More

Fig. 39 (a) Fatigue crack propagation regimes and (b) crack growth rates of wrought aluminum alloys. L-T, longitudinal transverse; T-L, transverse longitudinal. Source: Ref 65 More

Fig. 35 Fatigue crack propagation curves for through-hardened M50 and case-carburized M50NiL. Source: Ref 47 More

Fig. 9 Fatigue-crack propagation in alloy 2048-T851 plate More

Fig. 15 Fatigue crack propagation data for 2090-T83 sheet, 2090-T81 plate, and 7×75-T6 sheet. Crack orientation, L-T (crack plane and propagation direction perpendicular to the principal direction of metal-working); stress ratio ( R ), 0.33. Testing conducted in high-humidity air (>90 More

Fig. 9 Comparison of fatigue crack propagation rates of BE and I/M Ti-6Al-4V as a function of the stress intensity factor range at room temperature in air. Stress ratio ( R ), +0.1 ( R = σ min /σ max , where σ min is the minimum stress and σ max is the maximum stress); frequency ( f ), 5 Hz More

Fig. 1 Variation of fatigue crack propagation rate, da / dN , with applied stress intensity range. Δ K , for MgO-PSZ ceramic, tested in room-temperature air (45% relative humidity) at a load ratio R of 0.10 and a cyclic frequency of 50 Hz. Data for varying load ratio (0.10 to 0.46 More

Fig. 8 Fatigue-crack propagation behavior of a number of MgO-PSZ ceramics and a copper-impregnated graphite material compared with that of similar-strength steel and aluminum alloys. Source: Ref 17 , 18 More

Fig. 10 Schematic representation of fatigue crack propagation behavior. In regime I the crack growth rate is low since the threshold for crack propagation is approached. In regime II the so-called Paris law is obeyed while in regime III the crack growth rate increases above that predicted More

Fig. 10 Plots of n and C from the Paris fatigue crack propagation equation, comparing noted microstructures in a number of steels with various quality levels and testing orientations More

Fig. 11 Comparison of n and C values for the Paris fatigue crack propagation equation comparing three grades of steel with various quality levels and testing orientations. No effect of strength level is shown. More

Fig. 13 Plots of n and C from the Paris fatigue crack propagation equation for A633C steels in salt water in conventional and calcium-treated quality levels and three testing orientations (LT, TL, SL). Comparison is made to overall scatterband of all carbon and alloy steels in air testing More

Fig. 42 Fractography of fatigue crack propagation at intermediate (region 2) and high (region 3) growth rates in steels tested in moist air at R = 0.1. See text for details about regions. (a) Ductile striations in 9Ni-4Co steel at Δ K = 30 MPa m . (b) Additional cleavage fracture More

Fig. 63 Influence of testing temperature on fatigue crack propagation exponent for iron-based alloys. Source: Ref 68 More

Fig. 22 Fatigue crack propagation behavior of modified 9Cr-1Mo steel (ASTM A387, grade 91), tested in air at room temperature (800 cpm) and at elevated temperatures (40 cpm). R = 0.05. Source: Ref 25 More

Fig. 8 Fatigue crack propagation results at 0.8 Hz in air with R = 0.5, for SAF 2507 in quenched and air-cooled conditions. Source: Ref 28 More

Fig. 11 Fatigue crack propagation rate as a function of stress-intensity factor range (Δ K in Zeron 100 aged at 400 °C for up to 5000 h, tested at room temperature (22 °C) at R = 0.5 and R = 0.1. Source: Ref 31 More

Fig. 67 Relationship between fatigue crack propagation performance and fracture toughness for laboratory-fabricated 2XXX and 7XXX aluminum alloy sheet. Mean crack growth life is that life averaged over four experimental conditions for each alloy. The four conditions were two frequencies, 2 More